One that I’d like to see is a more in-depth sorting option for posts (allowing you to see for example top of December 2020, or top of a specific day). A custom date range selection would be best. I remember this being a frequently requested feature in the early days of reddit, and they never implemented it.
This is a requirement for the Markdown format, which was originally designed for text files where some text editors might not handle text wrapping very well. We could add a WYSIWYG editor later on like the one the Reddit redesign has, but it’s not really a priority currently.