Completely understand about the creator info, on here I see it being a bit more important.
I’ve found I don’t miss the heading. The only downside is I had to add special styling for the new posts alert. It does mean there is an odd space between the topic list and the top buttons, where as the heading would provide that spacing without feeling odd.
Decided to play with it a bit and tone down the category colors, and use the primary color for the replies.
I also felt the category color on the left was a bit strong. After the changes, they still are easy to recognize, but much less strong.