I've been using Musicbee for a month or two now, and it's an absolute dream. Really seems like it's been made by someone who's used other music players and thought hmm, that would be useful, and added it. Every time I think 'it would be cool if I could do that', after a quick search and some playing around it becomes reality! Incredibly intuitive.
Adding all the random folders I have has become a lot less tedious as it's fun finding out all the info about an artist to put in custom tags now. It's made me relisten to a lot of world music compilations i've got as I've begun adding locations alongside all the usual tags, so I can filter by continent/country/state/town. That might take some dedication, but it brings alive another angle to a musician. Or removing all browsers and columns for a screen solely made of album covers looks quite classy.
Lots to discover, many thanks!!