How can I sync my Music Library with iCloud and iPod without Losing Songs?

Hello! I've had Apple Music for some time now, but I'm getting back into owning my music. After much time, effort, and money, I have purchased every single song I've ever had in my Apple Music Library up until this point. However, it takes up a lot of storage on my Mac. I have uploaded the songs to iCloud Music Library to free up space, however because I have an iPod, if I remove the downloaded songs from Apple Music, when the iPod syncs it obviously deletes the songs that were on the computer.

Is there an easy workaround to this? I have an external hard drive for my music library, however I don't want to have to plug it in every single time I add a new song to my library and want to sync it with my iPod.

My current thought process is to just buy a Mac mini with a 2TB hard drive and just have my entire music library be on that device.. but are there any alternatives you can think of?

[Re-Titled by Moderator]