Which of these old iTunes directories can I delete?

[kat.hayes]

I have a drive with lots of old iTunes backup music folders, and sub folders, and I am trying to figure out what I can delete without causing issues. I also have a folder that I currently have Music pointed to for the Library. Can someone please provide any feedback on potential issues with deleting the following from the older folders that are not part of my current Music Library:

Album Artwork

Automatically Add to iTunes

iTunes Library.itl

iTunes Library Genius.itdb

iTunes Library Extras.itdb

Audio Music Apps folder - Inside there is an empty Custom Icons folder, and a Databases folder with a Tags folder inside it with lots of files names with lots of numbers followed by .tagset extension

There is also a Plug-In Settings folder with a subfolders named Alchemy

Thanks!