Personally I like the idea of being able to distinguish one Xenos from another if I can't make it out visually. Adds that small layer of decision making in regards to which race is a bigger threat on the campaign scale of things
I don't think there should be different color coding because it wont take long to learn what wants to take your scalp or who wants to watch your back
The campaign map showed the faction colors (red, green, light blue), at least in terms of territory, though I suspect it can be just as well used when trying to indicate friend from foe. It should show there name in that color, or just as red. Either way, you can easily see who is who.
Do you mean having their silhouette turn red or green like in Left for Dead? Or highlighting their username in red?
In PS2 it makes Vanu and charlie squad purple guess how many times I team killed charlie before I changed all enemies to red.
I think that the character models should be obvious enough to tell friend from foe. I assume they'll just make the targeting reticle red or green depending on who or what you are pointing your weapon at. I think it would ruin stealth if you are a Kommando Nob trying to blend into the grass or a tree (since you have armor that is cammo), but then you are spotted by an SM because you are a fat red blob even though you appear camouflaged to yourself. This can be expanded if there is a night cycle then people would be essentially illuminated at night. Furthermore, if people are brightly colored as enemies, then it takes less skill to spot them if they are intentionally trying to avoid you and run at the edge of your vision.
Color-wise, we will probably have default colors per factions but let the player choose all-red for enemies like said prevously in this thread. We will try to use different shapes and icons to reinforce the distinction. An additional thing we are looking into, is the ability to customize the colors used as well (mainly to allow colorblind people to pick colors they can distinguish).