hey, Dutch Ghost, nice story there. Though the robots rebellion idea might be a bit slippery because destroying robots somehow doesn't give so much satisfaction (even if they look like a young Arnold Schwarzenegger) as slaying various living entities (yay!! bloody mess!). But all the contracted mercs and raiders that You mentioned seem to deal with it.
It would also be cool to have the possibility of choosing to be an evil heartless scum and not to lose all the fun because of that (as it was in F2 where a do-gooder gets a lot more opportunities, experience and so on). Maybe even play on the "Combine's" side and be a contracted mercenary, vicious raider, blood-suckin mutant, killer cyborg...well, You know what i mean. I think the fact that there are so incredibly many ways to make your way through the game makes it one of a kind. Makes you want to play it over and over.
Also, the experience points system used in Morrowind, that lets you improve your skills by making use of them would be an interesting addition to the one used in old fallouts. It gives a nice "evolving effect" to character creation.
IMO there couldn't be a fallout without the specific sense of humour (the ghoul with a tree on his head is simply one of a kind!). Easter eggs, dialogues, descriptions, situations, people you meet, etc. are just funny in the best way.