Most of these have likely been addressed and are collecting votes....
1. Make membership optional.
2. Allow readers to like, subscribe and comment without having to signup for membership.
4. External URLs for Privacy / Terms and Conditions upon Signup.
5. The ability to add external URLs to blog navigation.
6. Perhaps the ability to color text with a hex code color picker in the editor.
7. More flexibility with regard to the layouts, i.e. having the option to customize the cover photos of posts.
8. Post Scheduling for publication, subscribers and social media channels.
9. Post preview option like the old blog.
10. The ability to limit the amount of posts per page, Pagination, Load more...etc...
11. Headers for Blog Posts.
12. Most Important to me: Expand gallery images!
13. Title & Descriptions for Gallery Images!
14. The ability to add Anchors. This is useful for lengthy structured posts.