When I long press any item it allows me to select multiple items (depending on a category it can be a song, album, artist etc), from there you get a popup and do what you want with the selection (play the selection now, create new playlist from selection, add to the curreny playlist etc.)
I agree, the default behavior depends on which category you have selected. My usecase is pretty simple, I usually just go to a directory I want and play everything from there (usually while driving) and skip what I don’t like, so I never really thought about it.
~/Games/{game}.
Also, do you keep game files in the prefix or outside it?
I keep my game files outside the prefix, so if you decide to change it, you don’t have to reinstall if something goes wrong. I never had such issue.