We need to be able to turn off the infernal "glow"/"aura" graphics effect of magian moogles, avatars, floating Cavernous Maws, telepoints, and Veridical Confluxes. Pay special attention to Carbuncle, because even when his model isn't displayed because of my "Characters Displayed" setting being at minimum, I see his blue glow.
I don't know if those things can cause blackouts, but if displaying other players' equipment can, then maybe. But they sure as hell devastate framerates for many users. The dread of avatar glows ruining my framerate has made me avoid SMN in group content now.
I'm buying a Windows 8 PC from a friend in a couple days with high hopes that a Windows 8 PC can do what my Windows XP PC cannot: display 2 magian moogles...simultaneously!