You could write a plugin(or rewrite the bp-code) that makes the name field not required and not a Core field and when submitted overtake the username value into that field?
at http://www.deeljezorg.nl we have custom made entry forms(TDOMF plugin) for users to enter their experience, stories and tips, it works fine, people can now easily add posts without the hassle of getting to know the wp-admin backend
same thing is done at tastykitchen.com, where people share recipies, also using a custom form for posting,
it’s disguising your blog posts into a more specific item
I had the GD Star Rating plugin for a buddypress install, did disable it again, for it slowed down the site too much, it had to load its own javascript library,
it worked nicely though, did have to tweak some settings to get it right, but it had it all, even made custom ‘stars’ to fit in with the site design.
