I am very much in favour of many of the aspects of this mod. 99% of the changes are excellent. Seriously, reading the description of the features, it sounds fantastic!
The one exception is using AP to do everything in combat.
I really enjoyed the turn-based Fallouts, and I am about to replay them again. I also enjoy first-person-shooters such as Half-Life. (And there have been decent RPG shooters like Deus Ex and Mass Effect.)
The way I see it, making Fallout 3 combat turn-based will simply make Fallout 3 into an inferior first-person shooter, and what is the benefit? None. It means that when you are playing the game and fighting enemies, your immersion is broken by the game not allowing you to move anymore or shoot anymore smiply because you have shot or moved recently. Have I run out of bullets? No. Has my gun jammed? No. Has my foot gotten stuck in mud? No. An arbitrary AP counter has decided I've used enough imaginary AP points and now I'm screwed.
Note that this isn't a rant against you guys - Bethesda made a mistake in the first place by including AP points in VATS mode. There's no reason why making a targetted shot should use AP points - you should be able aim at people's legs or arms or heads as much as you want. The cost should be that while you are doing a targetted shot you stand still and are vulnerable to being shot, and also the chances of hitting a specific body part are low, compared to normal aiming where you merely try to hit the enemy anywhere. Unfortunately, Bethesda decided to make targetted shots "bullet time", where everything goes into slow motion, and where you only take 10% damage. This meant that VATS mode was so extraordinarily powerful that it needed action points so you wouldn't use it constantly. Get rid of the slow motion and the 10% damage and you don't need action points anymore.
If you use a mod such as "Fast VATS"
http://www.fallout3nexus.com/downloads/file.php?id=1650 (or the earlier, buggier "real-time VATS" that is mentioned earlier in this thread), and combine that with "Simple Action Point Recharge Mod"
http://www.fallout3nexus.com/downloads/file.php?id=210 you can make it so that clicking the VATS key gives you a simple targetted shot. The game is paused while you choose a body part, but once you have chosen you fire your gun in normal real time, and your enemies are still running around and attacking you in real time. If you want, you can then do another targetted shot, and another, and another. This is dangerous, as while standing there you are vulnerable, and it makes far more sense than having to wait an arbitary amount of time for a magic bullet-time meter to refill.
It might also be interesting if "Fast VATS" and fast action point regeneration was combined with having all guns completely use up the Action Point meter when you shoot. This would mean you would only get to fire one single shot (or a three-round burst with an SMG) per press of the VATS key, but then after firing that shot you could immediately choose to use VATS again. The action point values of weapons would become completely meaningless, but that's OK because in-game the weapon descritpions don't mention the AP value, only damage.
In Fallout 3 the agility stat isn't terribly useful - your action points are determined by 65+ twice your agility. A player with average agility of 5 has 75 action points and a player with the maximum of 10 agility has 85 action points. I'd like to scrap action points altogether, and make Agility affect the player's movement speed and your skill points for all combat skills. In Fallout 3 the only combat skill affected by Agility is Small Guns, while in the old Fallout games Agility affected everything. I'd like to see that back.
(Fallout 3's system of "small guns use Agility, energy weapons use Perception, big guns use endurance" is absurd. Skill points for all weapons should be affected by Agility, and aiming all weapons should be affected by Perception. It's cool to see you've already implimented the Perception aspect into the mod.
JayTheGay's experiments with altering the animation speed of firing/reloading weapons seem quite promising. It would be great if Agility could be used for that, but if not, I'd be happy with Agility just affecting player movement speed and stat boosts to combat and sneaking. I'd much rather see the Agility stat used for that kind of thing, rather than "action points" which make no sense in a real-time game.
Down with Action Points! Up with risky targetted shots!