When I chose what server to use when we did the great chatroom migration, I specifically avoided quakenet. Whenever I seem to use it in the past it was plagued with netsplits. I chose gamesurge as I found it to be very stable and supported mibbit.
IRC chatrooms work best when you idle in it. Conversations arnt happening 3600 minutes a day, which is why people leave their chat client open (idleing) and when conversation starts you just join right in.
In the future I would move us to an XMPP (Jabber) server, it opens up the possibility to use things similar to live streaming and voice chats.
Edit: I just remembered that someone was working on a civ 4 mod that allows you to use the chatroom in game. I do not know if it was ever finished or not, but I do code in python so I might be able to pull something together if needed.