Hmmm... that gives me an idea.
A (gui, I guess.) required for certain servers, and a mod for servers to require this mod. (IF server detects that you don't have the mod, you are auto-kicked. :D?)
If the servers have this mod enabled, then it will require certain settings to be on (i.e. no-crosshair) to be enabled/dissabled.
Gui is keybound, open the gui to see the server's required settings.
If the settings don't meet the server's requirements, you get (loopkilled, forced spectator, no spawn, etc.)
IF the settings are fixed to the requirements, you are free to play.
Have it also detect F-Zooming.
If you f-zoom and the server says you're not allowed to, you get a kick/small ban.
Would that be possible?