For forum software, I would like to suggest XenForo as a replacement for IPS.
I use 2 other forums that use XenForo, they both work great.
XenForo:
Pros:
BBCode!
Users can switch forum themes,
"Social Groups", small user run subforums, the founder of SGs can set users as Social Group Moderators, SG Mods can only do stuff to a SG they are a mod on, I run 2 SGs on a forum that uses XenForo,
A signature system where users can put spoilers in the signature that can open to have loads of stuff,
Nameable spoilers!
From the research I've done, XenForo seems to be cheaper than IPS,
Cons:
There will be a bit of downtime for changing the software
No custom user titles, but there are small banners below your name that you can choose from,
Literally nothing else.
IPS:
Pros:
I can't think of anything.
Cons:
Literally everything.
For the reasons I added there, XenForo is obviously better