Humans- Stay the way they are now.
ghouls- most humans dislike you at first but super mutants are neutral. Regenerate health when irradiated.
Super Mutants- Increased health, melee, and unarmed but humans and ghouls dislike you. Lowered gun skill and energy weapons skill.
Another thing that would be awesome is having factions for each of the races, like the NCR and Caesar's Legion in New Vegas and each race would have at least 2 different factions and there can be more than 3 races or there can be different sub-races. For the humans, there could be a wastelander class, that has better weapons skills and the other sub-race could be the vault dweller class, that is more of a people person.
A great way to start the game would be making your character with the S.P.E.C.I.A.L. skills and the race and sub-race and then going on to training with a coalition force and then when a giant battle occurs against an unknown faction (and the faction is joinable later in the game), the player is knocked unconcious by a large explosion the player is left for dead and then awakes after the battle and must travel to one of several settlements near by to stat the story and the story is influenced by race and faction.
The location for this game should be San Fransico and the brotherhood of steel and the Enclave should be major factions
Thanks for your time spent reading this.