I don't think the intention is to recreate the gameplay of Fallout 1. I think it is to recreate the world and story of Fallout 1.
I've just done a post on how to improve VATS mode. I won't bother repeating that here, but yeah I think that may help to make the game a bit more like "a decent sandbox FPS like STALKER".
Some aspects of Fallout 1 can be revived, such as certain aspects of the SPECIAL and skills system - tagged skills giving you skill points for every point invested, less skills points each level up, perks every few levels rather than every level, perhaps traits too... Fallout 3 lets you be a jack of all trades, you can become reasonably profficient at absolutely everything, while you couldn't in Fallout 1. And I felt that Fallout 1 was a more interesting role playing experience.
(I understand why Bethesda went the jack-of-all-trades route - many people that buy the game may not even finish it, let alone play it repeatedly. They didn't want the average consumer to only see 1/4 of the game's options due to skill choices. What they should have done is made it so that when you play on Hard or Very Hard mode you get less skills points. System Shock 2 pulled this off well - in normal difficulty you have enough points to be awesome in a few things and OK in other things, but in Hard mode you are forced to specialise.)
The story and setting of Fallout 1 was great, and it had good characters and dialogue. Exploring a Mad Max style post-apoclyptic world... trying to find the water chip to save your home... discovering there is a threat of super-mutants... discovering the mutants are not merely results of radiation, but actually the FEV, and the mutants plan to evolve everybody... it wasn't deeply complex, but it was satisfying.
I felt Fallout 1 had the best story and setting. Fallout 2's wasn't bad by any means, I really enjoyed Fallout 2 as well, but it was less focused, it was all over the place, there was so much choice and so many options and so many quests that the "main quest" of finding the GECK seemed almost irrelevant.
In Fallout 1 the sub-quests worked well - you were looking for a water chip, you didn't know where to go, so you explored each location to see if you could find any clues on where to find a water chip, and while doing so you tried to help out and solve problems wherever you happened to be. Sometimes you'd have to backtrack or go out of your way a little bit, but generally speaking you had nothing better to do since you didn't know where to find the water chip.
Fallout 2 took that idea a bit too far... the "I don't have anything better to do" idea was stretched to rgw limit. Just cause you don't know where to find the GECK, doesn't mean it makes sense for you to become a porn star or a gangster or sell your comrades into slavery or whatever.
Fallout 3 suffers from this even worse - most of the time you know where you need to go to continue the main quest, and so to do the sub-quests you have to conciously decide to ignore the main quest. "I should be trying to find my father... but instead I'm going to visit a minefield or a robot factory or investigate the history of a place, and report back on my findings to someone in the very first town." The fast-travel ability stops all that travelling around being too much of a hassle, but when you think about it, you are zig-zagging all over the place to do very minor things, when you should be worrying about more important stuff.
Anyway... back to the subject of the viability of a Fallout 1 remake. I think the big issue is figuring out how travelling outside towns will work.
I've heard of the possiblity of some mods making Fallout 3's "fast travel" system include random encounters. So if you try to instantly teleport from one place to another you may find yourself suddenly warped into an area where you have to fight some raiders, or meet a wandering merchant, etc. If such mods are created, then a similar system could be used for ALL travel outside towns in a Fallout 1 mod. This would allow a very large (mostly empty) wasteland.
It would also make the game far easy to make - the modders would simply have to make the interiors of towns, and would not have to bother making an outside wasteland. All travel between towns would be fast travel - when the player attempts to leave a location the map screen automatically pops up and you choose where you want to go. You can travel to any place you have heard of. (At the start of the game one or two locations near Vault 13 would be automatically filled in on the map so you could travel to them.)
True, this means you are unable to wander off in a random direction and just explore, which is a shame, but in a dangerous post-apocalyptic desert it makes sense you only travel when you have an idea which direction to go. It also means that those that have played Fallout 1 before will not be able to go straight to the water chip! (And I know there are some peole that do that kind of thing - dirty cheating Fallout 2 players that head straight to a certain outpost and pick up Power Armour and powerful weapons right at the start of the game, shame on you.)
80% of the space between towns would not have to be created, since it would be represented purely by the PipBoy map screen. There would also be a few detailed outside areas, that would be used for random encounters. When you have a random encounter while travelling you are teleported to one of these detailed areas - a rocky desert, a sandy desert, a ruined cityscape, a polluted river, etc. If the players runs close the edge of this detailed area then the map screen automatically pops up again and you can continue your journey.
These outdoor areas for random encounters would have to be quite large - so that there's something interesting to look at in every direction - and there would have to be quite a few of them, say 20, so that it does not look like every random encounter occurs in the same place. Of course, in old Fallout 1 every fight with random Raiders DID occur in the same place, if I remember correctly, but it would be nice if that was somewhat avoided. If the players runs close the edge of this detailed area then the map screen automatically pops up again and you can continue your journey.
If it turns out that random encounters during fast travel is not possible (oh no!), then the alternative would have to be a "shrunk" Fallout landscape. Then the player has to walk all the intervening space between locations, just like Fallout 3. I'd expect the distances between locations to be about twice as large as Fallout 3, so the wasteland seems a bit emptier. It would still be somewhat unrealistic, since the player would be able to walk from one city to another in about 15 minutes, but then Fallout 3's time is accelerated anyway, a day lasts just a few hours. And people expect that kind of thing from the RPG genre anyway - look at the Final Fantasy games, you leave a city and run across the "World Map" and get to another location in a few minutes. People know that the distance travelled is representative of a much larger distance.
