You can't do that.
If you do that, you'll get confused if you have a 4-player (or Vs. 6 Endurance match) skirmish.
No one would be able to tell what is what.
It is likely that he'll have a few color schemes (at least six) available. Which ones do you think?
The ones I think are:
-Default Blue on Blue
-Red on White (as if using Rush)
-Dark Red on Gray (mimicking ProtoMan)
-Black on Gray (mimicking Bass)
-??
-??
What do you guys think?