i tried to contact a well-known developper to have an integration with wpforo (here you are his anwser) :
there are a lot of major issues with expanding WPForo that boil down to: very hard to expand because of a lot of inconsistencies when it comes to coding and few available hooks for other plugins to hook into.
1. Topic Prefix (voir in attachment): my plugin relies on taxonomies, but that will not work with WPForo, and it would require a new DB table and changes that are currently not possible in WPForo.
2. Quantum Theme: there is no way to do that because it was made to replace bbPress templates. For WPForo it is possible to have new 'skin', it is 100% coding from zero to do it.
3. Forum Notices: this is mostly possible to do, but again, the severe lacking hooks in WPForo in critical locations, makes most of the notices hard to position.
4. Toolbox: some stuff can be done, but a lot of things would be hard to do, because, again, WPForo lacks hooks to do things.
The whole theme in WPForo has less than 50 hooks in all templates, and there are many places where hooks are needed and not available. Also, in many places the same thing is done differently, so displaying the topic title, for instance, doesn't work the same in every place, and there is no way to control it. A lot of things in WPForo are halfway done, and extensibility is added only for what WPForo authors needed - like the necessary evil type of thing, extensibility was not high on the priorities list.
While bbPress does have a lot of issues (database structure is the major one), it excels in the possibility to be expanded and built upon, because hooks are everywhere, it is consistent in the way it works, it follows WordPress standards. WPForo fails in all of these, and while it has a complex database structure, it also lacks in several areas, and it is hard to expand upon. The ideal forum for WordPress would be 50% of bbPress, 20% of WPForo, and 30% new stuff to make it work properly.
VERY VERY BAD