Can I delete unused files in iTunes without affecting my music library?

I have a large music library (130GB) which I've built up over the years from buying iTunes, copying CDs, etc. I've bought a new MacBook and am now running Music in Sonoma. I am currently using Apple Music so everything is in the iCloud also. I eventually want to stop paying for Apple Music (maybe go the iTunes Match but undecided). Ultimately I want to delete all the unused files that have built up in iTunes (I have deleted old apps and iPod folders already) but I don't know which one I need to keep and which ones I can delete. I'm estimating there is 30GB of unused files (Album Artwork, etc.) that are not being used but I don't want to delete anything that will mess up my library. Am I okay to delete everything that is not my Music library (1 file) or do I need to keep the folders, sub folders, etc. Any help is gratefully recieved

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