Not sure if you still see replies to this thread but is there an option to store metadata (mostly images) in the folder or a subfolder? For example this is how Jellyfin is storing it if you tick the store metadata in folders option. https://i.imgur.com/F2ku5wa.png
It stores folder.jpg (main image), logo.jpg (logo), background.jpg (if you use backgrounds/headers) in the main folder and can also store all other metadata in a .nfo. Sometimes it also stores metadata in a subfolder for example the episode thumbnails are stored in a subfolder.
I think this is an important option for a proper collection, one reason is because an emulator or emulator manager might use these images themselves to populate their navigation menus which if they're all hidden away in an romm database, won't be seen. Another is that it makes browsing your collection in a regular file browser a lot more visual and aesthetic
Sure I'll do that shortly, appreciate the reply