ZDoom

Nitpick alert! In this case even without a point.

In Hexen.wad, the player class sprites (CLER*, MAGE*) are blue, but the menu sprites (M_CWALK*, M_MWALK* lumps) are red.

I'm drawing some confusion because original Hexen shows red for both Cleric and Mage in its selection screens. Whether that is the case, I honestly don't know. (I don't play DM so I plead ignorance.)

The default colors are as such:

Doom marine: Green
Heretic sidhe: Green
Hexen cleric: Blue
Hexen fighter: Gold
Hexen mage: Blue
Strife mercenary: Brown
Chex warrior: Light blue

This is all very blatant if you look at the class definitions on the wiki, where they all have their eight color sets enumerated.

For some reason, Blue is chosen for Cleric and Mage, instead of Red in Player Setup. The Fighter is fine as is.

Edit: I think it's worth stating that the default color option should be labeled default in Hexen, because the classes have two different colors and that initial option can confuse people.