The problem is, while the mods might fix some balancing issues, alter some of the game's vanilla effects, add some classic Fallout material and such, no mods have or probably can be made to fix the main issue; the bad storyline, the terrible dialog, and the fact that the world in Fallout 3 just doesn't plain work. There are more raiders than civilians for example, there are no economies other than four random trading caravans and random people out in the wasteland who just stay at one place or wander around but don't seem to do anything like collecting things, farming or anything. Only the traveling doctor seems to make sense. Its not that they could have added such stuff as there are plenty of abandoned farms around that could have been turned into working farms. And the settlements... the less said about them the better.