I've been wanting to start a discussion for a while now in which you share an aspect of the Mass Effect universe that you not only think is bad ass, but that could also be used in some way in the next games. If you have a link to the Mass Effect wiki page, even better. I'll start with one of my favorites; The League of One.
Huge fan of the Mass Effect series.
I would like to see the game expand beyond just playing a Human. I particularly like how the first Dragon age game allowed for various races each with a unique opening that was relevant to the overall storyline. In that way you could play as a Solarian, Asari or Drell etc.
Since there have been multiple cycles of Reavers you could easily set the story in an earlier era when humanity was primitive.