A quick recommendation I’ve been using this for the last year and once you understand the process, it is such an awesome music tagging app for individual song and it is free of charge!
While it might have a few clunky bugs here and there but it is one of the best I’ve tried.
I also use MusicMaster (Mac) for batch tagging conjunction with Onetagger.
ps. I’m not affiliated to them.
I agree, it has potential but is a bit buggy in my experience too.
Honestly, IMO the best thing for managing tags & playlists is Rekordbox and it’s FREE and it’s well supported and I don’t need to use anything else to get the job done.
(Not perfect and does take a bit of getting used to, but nothing comes close imo)
I’m not affiliated to OneTagger or Rekordbox 
Thanks mate, I’m gonna check it out!
I need to tag song by song by the sub genre/mood etc and I love the onetagger as i can do keyboard shortcut to it.
