Looks nice, except the active topic with preview ... This looks too clusterd. I prefer a topic preview in a mouse over popup or an option to disable the text preview.
I agree it looks a bit cluttered.
Too add to your suggestions:
- Maybe a divider between topics will help separate them better visually
- Perhaps collapse the post content (show all/none), tho I like the rollover idea, too
I wish I could remember how it was in Classic, because that seemed to work nicely...