Aww. I mean, I appreciate all the extra work that would have been required to implement as comparatively small a part of the game as a non-humanoid squadmate, but all the same... I would've really, really liked an Elcor companion. Heck, you don't even have to give him guns, and you can just make him some sort of extra-powerful biotic or something to make up for it. Not only would it add variety to the available selection of squadmates, but think of the character interactions!
"Reaper. A label created by the Protheans to give voice to their destruction. In the end, what they chose to call us is irrelevant. We simply... are."
"Defiant outburst, Sovereign. The Protheans disappeared fifty thousand years ago. You could not have been there. It is impossible."
"...You're really killing the mood, you know."