[SUGGESTION] A practise/chillout/casual server request

Weapons damage = 0 would be the easiest solution , but I think that you don't need this. Maybe you want to show something or i don't know.

Maybe instead of that just godmode for everyone?

-> Kick the trolls

Would be nice to always have there someone (an admin?) who can easily kick the misbehaving players and take care of the rest. I don't think any admin would be pleased to be non-stop there, so maybe a bunch of trusted players who like the idea, plays there often and would have the possibility to easily kick or ban anyone who is spoiling the fun.
maybe some system of warning players from server. A guy gets an on-screen text:
"you are being watched - start behaving or you will be punished".

If a guy is still trolling around he gets his punishment. First 2 times: kick, third time: ban for 1 hr, then ban for 1 day, ban for 1 week etc...

I bet that would work great and protect the good idea behind the server.

Sounds like a 24/7 peace party - fun!
Maybe you could use the peace maps , they have zones we you are not allowed to frag and fun stuff. Good old times
Enable cheats?

Peace zones - GREAT IDEA!
In the peace zone, shooting is disabled. You simply hide your weapon and can have a nice chat without being shot. Borders of the zone should protect the inside from projectiles.
Cheats - why not? If this won't spoil the game...