If races were implimented IMO it would ruin fallout forever
I think you're right, it would be ruined if Bethesda went about it how they do in the Elder Scrolls, where race matters only in certain attributes. But, if Bethesda actually put some focus and time into it, and made races more than just attributes, Fallout would be bettered and maybe even progressive in the fact of choosing a certain race actually meaning anything. I don't think I've ever played a game, where they had the choice of one race to another, and it made much of a difference.
Bethesda could change that, in Fallout 4 with enough focus and effort.