Hm, some kind of caching might be a good idea to add. Granted it might not matter as long as few people use it, but it does double the load from users with the script, since every page load causes a second page to load.
Another feature that would be nice is to be able to choose which communities appear. I currently have more than a screen worth but most are ones I don't really want to have there.
And perhaps also rename them (to make Lemmy communities a bit less ugly, for example I have "askelectronics@discuss...." and "[email protected]...." showing up now.
Hmm... I might work on this a bit, since I realize this is a lot to ask :-) If that's alright.
I'm not an experienced userscript dev though.