I don't recall when/where I read it but IIRC there was supposed to be an option going in for disabling the display of any player characters other than yourself. That, so far as I can tell, hasn't gone in it. However, I'd like to suggest something along those lines.

#1 A drop-down menu labeled "Display players" with the following options:
A. None.
B. In my party.
C. In my raid.
D. Up to

#2 A slidebar below the Display players that goes between 1 and let's say 40.

A second option/feature I would like to see is a separation of Object Distance and the distance at which player character models are drawn. This way we could crank up the Object Distance as far as it'll go and see mobs in plenty of time while turning down the Player Distance so that we don't have to deal with the game engine trying to draw/render the 30 or 40 who are so far away from us that we can't see them due to walls/buildings in the way when we're in major cities.

Just a couple ideas.