The nameplates in this game appear to be a noticeable source of lag, especially in fuller rooms. It seems the icons on the nameplates are unoptimized, and take up drawcalls even when not visible. Disabling nameplates in full rooms can often gain me quite a lot of FPS.
Ironically, the performance indicators have only made this issue worse. It's demoralizing to have only one material on my avatar, but still have the nameplate above my head take up 20+ drawcalls (which is more than twice as many as public world avatars are allowed to have!).
Almost every update tacks on something new to the nameplates. I think it's high time that the nameplates become more optimized.