While I think it'd be great to see an all alien Mass Effect game, I just don't see it happening.
Yeah. It's not like they're full fledged characters or anything. Tali, Garrus, Wrex, Liara, they're just mere uninteresting peons next to the perfection that is James Vega. I can totally understand why out of all the characters that could have gotten their own dedicated story, Vega was the obvious choice.
My opinion? He's just another over-muscled male space marine that I've seen many times already.