I also have a question that you might know the answer to. Is it possible to limit access based on BuddyPress types. I have found no plugins that does this, so I am wondering if this would at all be possible? To use BP Types would give a lot more flexibility than using roles. I have also found that it seems impossible to allow users to select roles on registration. There are a few plugins that are supposed to allow this, but it simply does not work. I wonder that it is BP that overrules the plugin and puts the user to default. If it was possible to limit content based on user type this would be a much more customisable function.
I also tested Ultimate member. I found that the way on ultimate member of controlling page access worked really great. (Unfortunately it was too limited in other ways and did not have enough functionality in comparison with BuddyPress, and the developer did not seem that interested in developing new features.)
For example when creating each post it was a widget for deciding access to posts/pages. And this worked on posts, pages and most other functions.
So it might be worth looking at their implementation for user access.
If it could work on BP Types that would be amazing!