Phil725 wrote...
Can't it be both though? Obviously the first step is complete functionality, but they've been wearing them for hundreds of years, that stopped being a concern a long time ago. I look at something like the shawl, and can't find any other explanation for it than a proxy for hair. Not like its beneficial in any way, otherwise the men would wear one as well. I just don't see why they would randomly settle on purple for no reason, they had a vote?
Of course my theory doesn't mean much in the long run, but that's the fun part about speculation. In the end, none of it matters, just a fun way to waste time 
I just thought of something regarding the prevalence of purple face masks: Rannoch's sun is orange, and purple filters would block most of the orange light, so it could be simply to reduce light input. And this in turn could be why their eyes seem to glow, though this frankly seems rather counterintuitive, and I haven't thought of a concrete reason as to why except it's easier for us, the players, to identify with characters when we can 'see' their eyes because of our human instincts (we generally don't trust people who don't show their eyes, and I suppose that could be extended to other races as well).
Soban wrote...
Acutally something that stuck out to me was the sameness of the suits that all the quarians wore. Then again. to quarians perhaps a tiny variation means alot more. When I look at a pic of a paintball team in uniform with masks on, I can tell every member apart. Most pepole who don't play paintball they look exactly the same to them.
The only reason the suits all look the same except for variations in color--except of course for Tali's--is because BW's art team didn't have enough resources (read meatsacks (read artists)) to give each individual quarian a unique wardrobe. They only made Tali's unique so that she would stand out because she is one of the main characters. In reality (well, if the ME universe were real), each quarian would personalize their envirosuits to their liking.