Thanks for the great plugin!
There's only 1 thing I'm missing and that's a role-based author slug.
role=editor ->author_base = 'editor'
role=author ->author_base = 'author'
role=member ->author_base = 'member'
etc., which would give this:
http://example.com/author/johndoe/
http://example.com/author/janedoe/
http://example.com/member/joeblogs/
http://example.com/member/janeblogs/
(which would then lead to their profile page)
I have tried numerous things myself to no avail...