I'm confused. You have posted in the forum for requests for the Android app, but it sounds like you are talking of features for the Desktop program?

Categories? There are only four Collection Categories and they can all be hidden, so they don't pose a problem. Lists that you can add to, but not delete from? That would be Media Types and Genres. I don't see how Media Types would be a problem, so that leaves Genres. Is that the one that bothers you?

Otherwise there are lists that you can't add to (or delete from), some of which are indeed rather long, for example countries and languages.

The chances of any updates to the program(s) seem rather slim, but if you are going to make requests it would probably be better if you were a bit more specific (and posted in the appropriate forum).