On my server we use emojis as the role names so they don´t clutter up chat, but they revert to a ? in a role if a member changes their nickname.
Additionally, to even use them, I have to use the uni-code (e.g \u00bb), which seems a bit strange.
If more robust support for them can be added, I´d much appreciate it; I imagine it'll get quite annoying to have to fix my server's role names every time someone so much as uses /nick.