I have no idea what a hypothetical ME4 would look like; I'm a bit too busy hoping they fix ME3. Honestly, if we actually get a decent ending that ties up the story we've got, I don't think a fourth Mass Effect game is even necessary: just because they can continue milking the universe for sequels doesn't necessarily mean that they should. I love Mass Effect, but after five years, I don't mind Bioware moving on to something new.