Most people use Lidarr so I just use it as well. Out of the box it needed some tweaking but other than that, it works quite well. Pulls tags from MusicBrainz and that’s enough for me. I have been thinking of trying out beets (or a web wrapper of beets), but haven’t gotten the time to do that.

I use beets in my setup and I am pleased with the results, keeps my library nice and clean. It is very capable by default and you can extend it even further with plugins. It will do fine importing well sorted albums and if you have a mess there’s also tag by filename and acoustic fingerprinting. You can use multiple metadata providers and adjust their weights for preference. It’s well documented and multiplatform (it can also be deployed as a container on a NAS system and manage of your imports). The biggest drawback is that you have to read a few pages of the docs before running it or do some dry runs.