I think the software as it is serves it's purpose. I see no need to replace it, but then it's not me who's supporting the forum. One thing that should be selectable is the display of all messages in thread, or the thread as it is now. Being able to display all messages in a thread would allow someone to catch up on a thread much faster than it is currently possible. But I've noticed I am not the only one with this remark.

Anyway, if the software must be replaced, for whatever reason the administrator might find apropriate, then by all means do so. After all, it's not the software but the members and hence the content that makes the forum what it is.

regards
Patrick