There's no point setting up our own IRC server now or in the future because the official HLP-channel would naturally be the place where people end up to when there's downtime. If the whole server is down and not just the forums, the IRC server would also be down and thus negating half of it's purpose. To make this as convenient as possible, all freespace related channels should be located on same irc-server or ircnet.
There's a good reason to keep channels like fs2source, nodewars, etc seperate. For example, the SCP people would not exactly love it if random discussion is taking place on their channel when they have a meeting. If there's already a channel called #hardlight somewhere, just promote its existence and people will eventually appear if they want to use irc in the first place.