1) Blog categories - Both to sort all blogs (admin defined) and categories that the blog authors can define and use in their individual blog(s)
2) Paid blogs - similar to the current pay to join club feature, this would allow blog authors to charge a fee to read their blog. Ideally, the blog author could decide between charging a subscription fee (access for X months) or a flat rate to read all their current and future entries to that specific blog.
3) Co-Authors - Allow a blog owner to invite another member to co-author their blog. Right now we have this per usergroup, but most people would rather invite a specific member to co-author rather than open it up to everyone in a usergroup.
4) Admin defined custom fields and users sort by these fields - just like clubs.
5) Default sort for entries - Allow admin to specify a default sort order. For example, my members would use blogs for both blogs (most recent entry first) and chapter books (oldest entry first, which would be the first chapter).