Add an allowed mods/clients list that's stickied in the general section of the forums. This will be helpful to players and save staff's time from answering questions, such as "Is Mod/Client X allowed?"
+1 I think there should also be a little message saying that there are mods that aren't on the list that may be allowed, staff just need to be asked. The reason I say this is because obviously we don't know about every mod out there, so harmless mods may not be put on the list.
I mean... that would imply that those are the only mods allowed, which isn't the case... although honestly it probably should be.
Maybe that should be the case. Maybe allowed mods should be its own subforum for the discussion of them as well as stickied list of the ones that are allowed. Then above the sticky and forum thread list would be an option to fill a form to request whatever harmless mod that a user would like added and a mod could look at the forms and add what they found to be harmless to the allowed list.
You're correct about the "only mods" allowed. Players should be allowed to request an administrator to add a mod/client to the list if deemed allowed.