Firstly, from what I've discussed with other members of IBIS on Plague Fest and on Steam, is the removal of BOT's.
Secondly, removing the Smoke grenades/ and limiting the frag grenade limit back down to 1.
Lastly, I feel there are too many Zm maps on the server map list, IBIS's Zm community has always strongly focused it's self on Zombie Escape. While I like having a few select Zm maps on the list, I feel as though it's taking away from the stronger aspect to the server and it's community.
These are my opinions, and they're subjective so feel free to way in; the server needs serious re-thinking.