I’m keeping an eye on gamevault as well, but wanted to include to Retro gaming. I also like a web interface which gamevault is not currently planning on having. Right now I am experimenting with Romm. I can create a category for gog games and download each game as a zip archive. Not fully what I want but it works. I love that for a lot of emulators you can play roms directly in the browser.

I also saw mention of gaseous games and Gameyfin but haven’t looked at them to closely yet.