>> a way to import files manually + tag them + move them into their final sitting place would be useful.
Perhaps I'm not understanding your situation, but what you desire seems to be exactly how I do it. (I'm only loading CDs and LP rips but would that matter?)
I don't have MC auto-import anything except under manual control (if that makes sense). And I don't have MC auto-rip anything. Too much happens that I later have to "fix" because I have a particular way I want my media organized and tagged.
For a CD I load it in the PC. MC sees it, asks if it should be ripped. I say yes this one time (auto-rip is never activated). It looks up the CD in YADB, and usually doesn't find it. It waits for me to either say rip anyway, or to type in the CD and track info, which I do. Then I rip (using whatever conversion mode I pre-set), which puts the new tracks in a temporary location/drive. MC tries to find cover art, succeeds once in a while. Ripping also puts the new tracks in a Recently... view. In that view I do the rest of the tagging of several standard and custom fields. Then I run a custom Rename process that assures all my tracks are named and located in a consistent way. MC renames each track and moves it to my library drive. Then I remove any bad cover art, and try to locate a good image now that the track tags are cleaned up. (Or, I scan my own CD's cover.)
For an LP rip, I'm starting with a folder of WAV files rather than a CD. I've already named all the WAV files consistently (I rip, edit and save them using Sony Sound Forge). I copy an album of tracks to a temp import folder which I tell MC to import AND to convert the format (to FLAC or MP3 or whatever I want) AND to delete the original tracks (which is why I COPY the tracks to the temp folder, preserving the original (actually this happens between two computers). I've set MC to understand how I named the files, so during import it identifies album, artist, track and song and puts them in proper tags. These tracks now appear in a Recently... view, where I do the same steps as with a CD, updating more tags and adding cover art.
The only automatic steps I let MC do are these, which are launched manually.
-- Search for CD track info and/or cover art, because it might help and if not I do it manually which I would do anyway if MC didn't try first. This is invoked by MANUALLY running Rip Disc.
-- Convert tracks from CD or WAV format to desired FLAC or MP3 format. This is invoked for CD by manually ripping, and for LP by manually running Convert Format.
-- During LP import, add tags based on file names per formula. This import is manually invoked.
-- Rename and move files per formula, manually invoked.
I might have skipped/misstated a step, doing this from memory, but probably you get the idea...