As a programmer, I think that if you moved the topics and posts table into the core application and made them available to the other application, the board would be better.
Basically, every app I've installed so far including the various apps that come with IP.Board (forums, members, messenger, blogs, tracker, calendar, gallery), have the equivalent of the topics and posts table. A member's profile has the About Me section (topics), and the profile comments (posts). The messenger has the messages (topics) and replies (posts). The blogs has entries (topics) and comments (posts). The tracker has issues (topics) and comments (posts). The calendar has events (topics) and could easily have comments to events (posts). The gallery has images (topics) and comments (posts).
Every app is likely to have this same basic structure: a single table for posts (so all content posted by members is searchable in a single table and a single table for threads (to describe this content).
Apps would have to have the ability to extend these core thread and post tables with new columns, but they should all be made to agree to populate the common columns when adding, updating, and deleting content. Note that you would need to introduce the concept of class to the core thread and post tables (that is, have a tag/type column and allow extension by adding columns or overriding the common columns for a particular instance of a class object.
The result would be global searchable content and lists (like View New Content) that can show all content ordered or filtered in a more efficient manner to the member. I want to be able to generate a single list of all content posted by a member ordered with the newest content first. I want to visit a community that has blogs/galleries/calendars/forums and just look at a single list of new content. I really don't want to poke around in various tabs to see if anything new has been added. I even want to see calendar events for the current and past days in this single list (so I don't miss birthdays or can see that I missed some community event the day before. Same goes for personal messages. It would be nice if they showed up as well in the new content list (although most members are probably comfortable with viewing the messenger as an online mailbox and don't necessarily gain as much by treating the member's messages as a private forum). Still, for the sake of consistency, I would treat messages as conversations (or threads) which is really what a forum is all about.
I'd love to hear back from you as to whether something might be done along this line in the coming year or so. If not, I might make a pass over the code and do it for myself. The mods would be extensive (although not as bad now that the software is more object oriented.
This is my biggest suggestion for the future.