Plugin development questions (import and metadata)

[phirestalker]

I am getting Gemini to develop some plugins to solve a few of my issues with beets. I have found success with one of them. A simple plugin to add or remove items to a list for a custom tag. I use it to add tracks to named playlists. Once tagged, smartplaylists can take care of it for me.

The problems I still need to solve:

1. I want MORE (data that is). For example, I would like gender, disambiguation, country (I'm sure there's more, and some may be already fetched, but they don't show on my tracks)
2. When I import music I want to scan all the tracks (to match easier), but only keep certain tracks (the ones I like) automatically based on a --keep-tracks option or a file in the importing directory with the list of tracks to keep. I realize I can do it track by track, but that is way too tedious compared to listing some numbers on the command line.

I have some questions after beating my head against the wall.
For the import, I have pinned down to use the import_task_choice event. The issue is, I have no idea how to remove tracks from the task so as not to import them. Can anyone point me in the right direction?

For the extra tags, I am not sure the correct way to do this. I have read quite a few posts and discussions about adding tags to files. I will table that for now and just be satisfied with them being added to the database. Here, I have no idea what part of the process to hook in to, and once there, what the heck do I do? I have been through many iterations with Gemini, but he gets caught up with old versions of beets, and not understanding the codebase or something. Any templates I can follow for this? Can I even do this with a plugin?

Sorry for the long post, but this has been driving me nuts. Thanks for reading.

[phirestalker]

For case 2, it turns out it is not currently possible. For that case, I would like to request it be added as a feature.
I see it as adding a commandline option like --keep-tracks or something, and extending the import process to allow for skipping individual tracks during import. I have no idea how much work this is or isn't, but I figured I'd ask anyway.