Great that you're getting users in on this.
Here are a couple of my personal pet peeves:
List items are indented way too much. Here's a screen shot from 220.127.116.1155 (308555) Public (CE Build ce-62.3.7750) on Windows 10.. Wish I could put a border around it but I couldn't figure out a way to do that here.
I'd change it in CSS, but AFAIK there's no user-accessible way to do that, and in any case it would only fix this for me, on that one machine. I can't imagine anyone wants the current behavior.
Cut/Paste and Drag/Drop of "paragraphs" often results in extra or missing "line feeds" at the beginning or end or the text you move.