I think some of it can be solved by updates to the Lemmy software itself. I’ve seen the issue with image rotation and my assumption is that Lemmy is ignoring the orientation EXIF data. Also allowing the upload of GIFs, or fixing it so the image picker doesn’t show them.

Then there are the laborious to users and communities when using desktop site which definitely needs a bit of streamlining. Sync for Lemmy lets you use the @ symbol to mention others, for example.