I understand where your coming from, but i dont think you should get Intel on a person just by magically looking at them.
I can look at you and think your from a certain country but until i ask you I can't tell your from a certain country, it should be the exact same way with tribes.
Organized groups will form there own tribe uniform, so you know Tribe A wears the brown cowboy hat with pink ass less chaps and a grass shirt.
or this other group wears the Truckee outfit for there uniform.
that's really all that is needed to make a tribe identification viable.
grouping can be the same, just wear the same thing as the rest of the group. it doesn't have to be high level stuff just wear same stuff.
Any non 1v1 combat will be a ridiculous, arduous affair if there are no easily identifiable means of telling who your friends or enemies are. It's tough sometimes even when there are clan tags if teh combat is fast paced. There absolutely needs to be guild tags.