I don't think it'd be incredibly difficult to make a Fallout MMO in the same vein as the original. But to get the MMO to really feel like the original would require an uncompromising attitude against most of the sissy traditions of current-day MMO's.
For instance, completely open-PvP is a must. You need to be able to attack anyone, anywhere, for any reason, or no reason at all, without anyone's permission.
Death needs to be permanent, so that people really think before they pick a fight.
Fist-fights need to be non-life threatening, unless your unarmed skill is above 100% or so. So if you and another player just brawl, you shouldn't be able to kill each other, but you should be able to knock the other person unconscious, and maybe steal everything on his person.
Corpses need to be completely lootable, all pockets need to be pickable, the emphasis on gear needs to be both strong and weak at the same time. People need to give a shit about their equipment while at the same time understanding that they probably won't have it forever.
The game needs to be a survival game first. Above all else. If you put the emphasis on combat, the game's just going to be a grind-fest bullshitty bunch of crap. If you put it on loot, same problem. Keep things personal and internal. Food needs to be an issue, in order to have a good economy there needs to be consumables. These consumables should be very player-driven, as in scavenging, but looting really shouldn't come into play except in PvP.
PvE needs to be de-emphasized. There can be NPC's, but there shouldn't be any lairs of bandits you can go camp, or anything like that. If there's to be combat, there needs to be a reason for it, not just for XP or random loot. The emphasis should be on PvP if combat is to take place at all. Having the emphasis on PvP means players are going to join forces in order to stay alive. You'll find a great deal of cooperation in this kind of environment, even if you do have lots of asshats running around shooting everyone in sight because they don't take the game seriously.
You shouldn't start the game with weapons. This, combined with the lack of possible death-by-fists mentioned above, makes the concept of brand new characters rushing into battle to kill people useless. You won't see a player dying, coming back as a new character to seek vengeance. Or if you do, it won't be an instantaneous thing, as he'll need to spend time finding weapons and ammunition, and the like.
Vaults can be neutral-zones. All players can be from Vaults, and there can be tons of vaults all over the wasteland, which will enable you to pick and choose where to start from. This might seem a bit weird, to have all PC's be Vault Dwellers, but Vaults make great n00b zones, and Vaults can be the only place where PvP is turned off, enabling new players to get the ropes without needing to fear for their lives. There will be some vaults that aren't n00b zones where there is PvP, so it won't be all vaults that are like this.
XP should be gained probably in a system resembling EVE more than anything. Ultimately, MMO quests are boring and stupid as fuck, and just lame in general. So aside from a few n00b quests to get some coin in your pocket when you first start out, there really shouldn't be many of these. Keep the interaction emphasis on the players. Keep the players talking to each other, interacting and dependent on each other, and suddenly you're actually taking advantage of the MM in MMO, rather than fucking stupid games like WoW which are basically single-player games that require a monthly fee.
The flip side to this, is that XP should only accumulate when you're online, outside of the non-PvP Vault zones. So that you only gain XP when your life is on the line. XP should come very slowly. Going from level 1 to 2 should require say, 10 hours of in-game time. Level 2 should require 20 hours, level 3 30 hours, and so on. Or something like that. The idea here is that XP is going to come, you don't need to do anything for it. I realize this seems counter-intuitive, like you don't have your own life in your hands, but this eliminates power-gaming where you just grind away. It also removes the incentive to go off and attack other players or otherwise take a combat-focused play-style in order to advance. Because of this, people will play the game just to play the game, without advancement in mind, so they'll be able to actually have fun, rather than grind, which only idiots have convinced themselves is fun.
Turn-based combat might be possible, though, honestly, it should probably be avoided. You could have semi-turn-based combat, like what you see in NWN or Fallout Tactics when turn-based is turned off, where action points still matter, but combat is done rapidly. You could even slow this down a bit, so that maybe the rate at which your Action Points regenerate takes several seconds rather than being really quick. You don't want passer-byers getting caught in the combat-zone or whatever it would have to be to make this work. That'd just ruin the fun of players. One way you could make turn-based combat work is to simply have a period of like, 15 seconds where all players get to make their turns, but they're all doing it simultaneously. Then at the end of the 15 seconds, the computer makes the moves you specified. This means everybody's actually moving at the same time, but you wouldn't know what they're doing until they did it. This brings in a whole lot of complications with it, but ultimately, a real turn-based system would just outright suck, especially in major battles of more than 30 people. Can you imagine two villages going to war with each other? One turn could take hours. That's not fun, even remotely.
The game should probably be ISO in perspective. FPP could work, but admittedly, the ability to aim manually does sort of put emphasis on combat, especially in a game designed to be specifically player-to-player interaction stuff, rather than NPC's handing out nonsense quests.
Ultimately, by removing a lot of the NPC's and keeping the emphasis on the players, and having a truly player-driven world, people will actually be able to affect the world, rather than current-day MMO's where they literally have no effect on the world, but simply engage in mindless quest after mindless quest, where the whole point of the game is to get as much loot and gain as many levels as possible. Removing that emphasis is crucial to making this game really feel like Fallout. Anything less completely neuters the game.
For instance, completely open-PvP is a must. You need to be able to attack anyone, anywhere, for any reason, or no reason at all, without anyone's permission.
Death needs to be permanent, so that people really think before they pick a fight.
Fist-fights need to be non-life threatening, unless your unarmed skill is above 100% or so. So if you and another player just brawl, you shouldn't be able to kill each other, but you should be able to knock the other person unconscious, and maybe steal everything on his person.
Corpses need to be completely lootable, all pockets need to be pickable, the emphasis on gear needs to be both strong and weak at the same time. People need to give a shit about their equipment while at the same time understanding that they probably won't have it forever.
The game needs to be a survival game first. Above all else. If you put the emphasis on combat, the game's just going to be a grind-fest bullshitty bunch of crap. If you put it on loot, same problem. Keep things personal and internal. Food needs to be an issue, in order to have a good economy there needs to be consumables. These consumables should be very player-driven, as in scavenging, but looting really shouldn't come into play except in PvP.
PvE needs to be de-emphasized. There can be NPC's, but there shouldn't be any lairs of bandits you can go camp, or anything like that. If there's to be combat, there needs to be a reason for it, not just for XP or random loot. The emphasis should be on PvP if combat is to take place at all. Having the emphasis on PvP means players are going to join forces in order to stay alive. You'll find a great deal of cooperation in this kind of environment, even if you do have lots of asshats running around shooting everyone in sight because they don't take the game seriously.
You shouldn't start the game with weapons. This, combined with the lack of possible death-by-fists mentioned above, makes the concept of brand new characters rushing into battle to kill people useless. You won't see a player dying, coming back as a new character to seek vengeance. Or if you do, it won't be an instantaneous thing, as he'll need to spend time finding weapons and ammunition, and the like.
Vaults can be neutral-zones. All players can be from Vaults, and there can be tons of vaults all over the wasteland, which will enable you to pick and choose where to start from. This might seem a bit weird, to have all PC's be Vault Dwellers, but Vaults make great n00b zones, and Vaults can be the only place where PvP is turned off, enabling new players to get the ropes without needing to fear for their lives. There will be some vaults that aren't n00b zones where there is PvP, so it won't be all vaults that are like this.
XP should be gained probably in a system resembling EVE more than anything. Ultimately, MMO quests are boring and stupid as fuck, and just lame in general. So aside from a few n00b quests to get some coin in your pocket when you first start out, there really shouldn't be many of these. Keep the interaction emphasis on the players. Keep the players talking to each other, interacting and dependent on each other, and suddenly you're actually taking advantage of the MM in MMO, rather than fucking stupid games like WoW which are basically single-player games that require a monthly fee.
The flip side to this, is that XP should only accumulate when you're online, outside of the non-PvP Vault zones. So that you only gain XP when your life is on the line. XP should come very slowly. Going from level 1 to 2 should require say, 10 hours of in-game time. Level 2 should require 20 hours, level 3 30 hours, and so on. Or something like that. The idea here is that XP is going to come, you don't need to do anything for it. I realize this seems counter-intuitive, like you don't have your own life in your hands, but this eliminates power-gaming where you just grind away. It also removes the incentive to go off and attack other players or otherwise take a combat-focused play-style in order to advance. Because of this, people will play the game just to play the game, without advancement in mind, so they'll be able to actually have fun, rather than grind, which only idiots have convinced themselves is fun.
Turn-based combat might be possible, though, honestly, it should probably be avoided. You could have semi-turn-based combat, like what you see in NWN or Fallout Tactics when turn-based is turned off, where action points still matter, but combat is done rapidly. You could even slow this down a bit, so that maybe the rate at which your Action Points regenerate takes several seconds rather than being really quick. You don't want passer-byers getting caught in the combat-zone or whatever it would have to be to make this work. That'd just ruin the fun of players. One way you could make turn-based combat work is to simply have a period of like, 15 seconds where all players get to make their turns, but they're all doing it simultaneously. Then at the end of the 15 seconds, the computer makes the moves you specified. This means everybody's actually moving at the same time, but you wouldn't know what they're doing until they did it. This brings in a whole lot of complications with it, but ultimately, a real turn-based system would just outright suck, especially in major battles of more than 30 people. Can you imagine two villages going to war with each other? One turn could take hours. That's not fun, even remotely.
The game should probably be ISO in perspective. FPP could work, but admittedly, the ability to aim manually does sort of put emphasis on combat, especially in a game designed to be specifically player-to-player interaction stuff, rather than NPC's handing out nonsense quests.
Ultimately, by removing a lot of the NPC's and keeping the emphasis on the players, and having a truly player-driven world, people will actually be able to affect the world, rather than current-day MMO's where they literally have no effect on the world, but simply engage in mindless quest after mindless quest, where the whole point of the game is to get as much loot and gain as many levels as possible. Removing that emphasis is crucial to making this game really feel like Fallout. Anything less completely neuters the game.
) in my experience tend to be control freaks, and marketing tend to listen to players whining on the boards far too much.
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