Some shows starting off a “squad” of Power Rangers is 3 (Jungle Fury, Ninja Storm). So I could do that and still have room for one more character.

So my Mass Effect idea could work.

My Dragon Age idea could work but they would be a little more fish out of the water technology wise.

Right now you only have heroes and villains. People like the Punisher from Marvel are antiheroes. They are not typical heroes nor are they villains in any way. Some heroes might call them villains.

EDIT: This point on random ramblings for ideas for this RPG pay it no mind or do up to you, no guarantees.
I might use Iron Punisher (my name for the Punisher in an Iron Man armor, I saw that at marvel.wikia.com), maybe 4 people like that. Iron Punisher, Iron Man, War Machine, Iron Spider (Amadeus or Peter), ..................maybe that is to much.