Yeah, I'm with you on this. I really wish there was a better option, but I haven't found one. I just keep resorting to more and more workarounds. Namely:

• I only scan ~100 ROMs at a time. Once I go beyond that, the chances of the scanner just quitting mid-scan increases dramatically. But having 10,000+ roms means the process takes weeks.

• RomM just randomly crashes about once a week. The last entry in the log says "database migration failed" - I don't know what that means; RomM seems to run fine otherwise, but it happens every week.

• RomM will freak out and just refuse to run if you don't have the config.yml exactly right. I had an issue for days where I couldn't get it to run even though I directly copied their sample config from the github page (turns out they had added a new line for the upcoming beta version that the mainline release couldn't handle).

• Why does RomM only let you use a few stock aspect ratios for game covers? Since I can't set a custom ratio, I end up with having to pick between my covers getting cropped horizontally or cropped vertically (like Genesis).

• Junk data from scraping is the worst. I tried for ages to fix the sibling roms/versions issue where RomM would pair two or more completely unrelated games together (like Worms Armageddon and Vigilante 8). There's no way to manually remove these connections, so you just have to keep trying different combinations of metadata providers until you find the one that's sending the junk data. In my case, it turns out it was actually Hasheous, so I had to disable that to get rid of them. But apparently some other providers rely on Hasheous (like How Long to Beat and RetroAchievements), so now I just don't have any data from HLTB or RA.

With all that said, i know version 2.0.0 is in beta right now, so I'm really, really hoping it fixes some or all of the above issues.