you mean they went from Green/Purple to orange being that these (NV Super Mutants) are the same super mutants from the 1st two games

I'd say yes, but only if i got to play as a supermutant. Seriously: transforming into a first gen would be just the kind of epic experience that New vegas is missing.

its like a hundred 20 years though since the vats got blown up im pretty sure any residual FEV is either dried up or taken away, though it would be epic to play as a super mutant or ghoul

I would love to see a DLC on them something like they're requesting aide need help to find cure to sterility being attacked by humans yada something like that.
While alot of people say they were in FO3 they were pretty much cannon fodder all the were there for was to be shot and you never really got to interact with them *excluding fawkes*.