Bearcut wrote...
Anyway... this is my take on Quarians.
1) They are obviously Mammals. (Hello, breasteses!)
2) Because they are Mammals, it's pretty safe to assume they have a birth canal of some sort, and that this would be conducive to breeding with another Mammal.
3) If they are sterile inside the suit, don't really have to worry about smell too much do we?
4) We can assume that their planet is darker - there has to be a reason for dark faceplates and glowing eyes, and I assume it's because their natural environment either has very low light, or a very long night cycle, and they evolved such advanced night vision that their eyes glow. Plus, we don't even know if they see in the same spectrum as we do. So there. Thats my take on the Dark faceplate.
5) I can't think of a Mammal without teeth, so we can assume they got teeth.
6) We can see through the masks a relatively human face (Eyes, Nose, Mouth below the Nose)... so they aren't gonna be too crazy, at least not in the face department.
7) Hair is a really a give or take. What is the evolutionary purpose behind long hair? Come to think of it, why does the hair on a humans head continue to grow..... oh right, we don't shed. Much.
8) Another reason for the faceplate is privacy. In the cramped quarters of the flotilla, they don't exact get any "alone time." The suits have become a psychological barrier of sorts and being able to hide their face is another part of that. Several generations of this have led to a sort of reverse claustrophobia (i forget the other term)
Yeeah. 
1) This would seem true, but then, somebody said the dev's had said Asari were aquatic... Of course, they could be aquatic mammals, but I'm pretty sure the devs said Humans and Quarians were the only mammals...?

2) Yep! (Also, the story with the bubble sounds exactly like a human birth)
3) Completely agreed, Tali would smell as bad as somebody fresh out of the shower, at worse. There's probably even a system that keeps fresh air flowing over their skin, for health reasons.
4) This makes sense (and is rather attractive, IMO), though Tali's eyes don't seem much larger than those of a human; Also, their planet is heavily populated by plants, it would seem, though there are many, many low-light plants on our world, which we would use as "the norm" (Basically made that last sentence redundant...).
5) That's a safe bet; Though, I would be sad I didn't get to use them, only eating paste...

6) Agreed 100%, again.
7) There's no room in those helmets for any crests; And they (especially as mammals) would have the exact same uses for hair as we would, though they also apparently transport pollen; So maybe slightly looser ("featherier" came to mind, although I just mean slightly different hair, not feathers...), or finer hair?
8) I'm sure that Quarians would have developed an anti-claustrophobia (too lazy to check Bearcut's real word), or, to be precise, I'm sure they would find the sudden change of everyone being able to see their face, and the naked feel of it (plus everyone staring, "OMG! DUDE, IT'S A QUARIAN WITHOUT THE MASK!"), quite uncomfortable and alien.
Going back to 4) and 8) for a second, obviously, the Quarians weren't used to people not seeing their face when they first created their enviro-suits; Thus, there must be another reason for having a dark faceplate. They wouldn't have changed from a clear plate to a dark plate (and some would still wear the clear, no doubt), because they wouldn't have developed that comfort for not being seen, and the discomfort for strangers seeing their face, if their faceplates were clear. So, considering the darkened faceplate must have been around since the very first enviro-suits, I would imagine it has a lot to do with their vision, and the seclusion is a side effect that's become part of every Quarian... Plus, those shining eyes are bound to have a pesky reason to be so damned awesome