I don't understand the rage this topic has created. Its a good idea. Its even been done before, a lot. Why is there any conflict with lore? In FO2 you can get a ghoul companion. In FO:Tactics you control different races: humans, ghouls, robots, cyborgs, super mutants and even deathclaws. There's also a mod for FO3 where you can pick a different start and race/faction, including but not limited to: ghoul, raider, slaver, android from the commonwealth.
Again, letting us play as a different race - great idea.
The arguments against don't make sense to me: you would be shot on sight? - 1) how is this different from playing as a human? plenty of nasty things want to kill you on sight, regardless of race - raiders, talon mercs, bounty hunters, animals, super mutants etc.
2) why would you be? oh sure there are some nasty bad racist people who would shoot you, but not everyone is like that! Broken Hills was a town where ghouls, super mutants and humans (and a talking plant and an intelligent scorpion) lived together. There is no reason to believe that everyone hates ghouls!
You can't be a ghoul because they are decaying corpses with bits falling off and most of your stats would be 1 - 2 points only? - Utter rubbish! In FO3 feral ghouls are some of the toughest opponents you meet. Roy Phillips was a police officer before the war. In 2277 AD he is still very fit, a decent fighter, NOT feral. It is NOT canon that ghouls are rotting corpses. It is only the racial slurs that people say about them in the games, the same people that call them zombies. Ghouls are not zombies. Not all ghouls are falling apart, and you don't need to be a recent ghoul to not be falling apart (see Roy Phillips)
Again, its a good idea. You should check out the FO3 mods that let you play as a ghoul if you're interested. And there is no reason to rage against ghouls.
EDIT: I found the mod I meant - FWE - FO3 Wanderers Edition
http://www.fallout3nexus.com/downloads/file.php?id=2761
https://sites.google.com/site/fo3wanderersedition/detailed-changes/01character#TOC-Alternative-Starts-credit:-Alternat