Actually the solution would be to remove that infection mode. More players would play TDMs/DMs/Duels and actually know how to clan war. I see too many infection mode rooms and it doesn't help improve the skills of players.
And as always the monthly clan war reward is terrible. No idea why it hasn't been changed. Award players with donator coins based on the points they get for their clans.
On room tags, the only sucky room tag I know of is [R]. The other tags aren't that bad.
The only way to keep this server alive is to attract other GunZ players from other servers. Making clan war active and competitive would pretty much repopulate the server. Once the new GunZ server by Emisand comes out fgunz will die unless fgunz plans to do a huge change to this whole server.