As long as the other human players are outside the screen, the indicator pointing towards them is good, very easy to know where they are, though sometimes hard to know how far away they are. But when your "buddies" - the other human players, are on screen, that colored little square beneath them is not enough. My suggestion is that all human players have different colored hats than the bots. Let your buddies have blue, yellow, black, white hats. that would be very helpful when you are in the heat of battle.

Not too sure about this one. Call me crazy but I personally prefer subtle markers for these things, and if possible, no markers at all. Markers and bright colored hats tend to fight against immersion, too.

Also the game system can't handle creating character appearances out of pieces due to speed optimizations, so adding e.g. 20 different hat colors for the 3 factions would require us to create at least 60 new character models, or, change the system..

Somewhat on topic about highlighting buddies, 0.98 features manageable player squads and Steam friend highlighting, the ground markers for these have different looks and intensities than the rest of the player/squadbot markers.