More easily bookmark or tag (star) music to be synced to a device

I have been using an Airsonic server (opensource branch of Subsonic) with the app Dsub on an android phone for a number of years.
When I want to sync music to my phone, I can do it 1 of 2 ways quite easily.
I can open the app on my phone and simply play it, and the music will automatically cache to my device.
Alternatively I can star the artist, album, or song(s) either on the phone or in the web interface on the server, and set the app to automatically check the server at a set interval for starred content.
I put my phone on charge, go to bed, and all my music has synced over night with very little input from me.
I’ve decided to try the equivalent in Plex, but I am shocked at how cumbersome this process is.
For starters, there’s no way that I can tell to see what content I have set to sync on the web interface, and I also have to specify the device I want to sync to. I’d prefer to pick what music I want, and based on the account I’m signed into on a device, automatically sync that music.
I also have to set the bit rate EVERY SINGLE TIME I go to sync a piece of music. Not only that, each time I add music, it creates an item in the sync list. I’d much rather have a default bit rate and just click sync once and be done with it.
What do other people think of the process? Surely I’m not the only person who has found this process cumbersome?

Edit: to further iterate, once I have starred content for an artist, it will automatically sync that content in the future when I add a new album for that artist. I don’t have to manually queue up the album to sync it to a device.

@“my.ninja” said:
For starters, there’s no way that I can tell to see what content I have set to sync on the web interface,

Yes, there is a way.

This screenshot is made with the hosted web app from https://app.plex.tv/desktop
If you use the local web app, it is done with Status - Sync

and I also have to specify the device I want to sync to.

Well yes of course you have to specify the device. Since you could have 20 mobile phones and tablets.
Syncing to all of these at once is not very sensible, because they all could have different demands due to their different audio quality, available amount of storage etc.

I’d prefer to pick what music I want, and based on the account I’m signed into on a device, automatically sync that music.

Could you explain that a little bit more? What kind of account are you referring to?
Do you want to use several Plex accounts on your phone at once? If so, why?

I also have to set the bit rate EVERY SINGLE TIME I go to sync a piece of music. Not only that, each time I add music, it creates an item in the sync list. I’d much rather have a default bit rate and just click sync once and be done with it.

It is certainly possible to create a Sync job, which syncs e.g. all tracks starred 4 or more.
This sync job will auto-update if you get more starred tracks or demote tracks from 4 stars to less.
So you only have to set it up once.

see for examples:

https://forums.plex.tv/discussion/comment/1572003/#Comment_1572003

https://forums.plex.tv/discussion/comment/1507260/#Comment_1507260

It’s late so I don’t have time to go into a detailed response, but I find your suggested method very un-intuitive.
By the feature request rules, I don’t find what you’re suggested would meet either of these criteria:

  • Keeping in mind that the majority of people using Plex are not advanced users, is this a feature that only you and a small number of other advanced users would use or is it something that will be used by a majority of the userbase?
  • Can your mother, father, wife, husband, sister, brother, grandmother, or grandfather use this feature without a CS degree?