go to combat settings and check the setting about show dispellable buffs/debuffs only(I think that is where it is and what its called). It will remove all buff icons but ones you can remove from the other members of your raid. This pretty much changed everything for me. That and insure you have the latest versions of any plugins you use especially buffbars and palantir. I still set graphics to low for raids but I can keep at least 15-20 now with high on.
Welleg - brandywine, Kelleg/Gelleg - Landroval
WARNING: leveling a warden may cause you to neglect your other characters.