A few years ago, I was delighted when we moved into a new place, and they had this tiny room that I was able to use as an office/ storage room for things I didn't want in my bedroom. Sadly, I don't have a space like that where I am currently, but hopefully, soon we'll be able to move out and into our own place.
A few little upgrades wouldn't go amiss, and for Music production and sound design, you wouldn't know yourself if you had something nice and nippy. It doesn't even have to be too wild: a decent GPU that's compatible and a good M.2 hard drive, and you'll be flying. You can get some info on your hardware you've got now, and there's a site you can add everything to, and it'll give you a list of compatible parts that you can pick up. That's how I managed to build my machine; otherwise, I wouldn't have had a clue. If you're buying a new CPU, it would probably be easier to buy a new motherboard too.
You're technically minded yourself, but if you want a bit of help, I don't mind looking into it too and helping you pick some parts.