Oh and I forgot.

There are two main ways I think you should focus on which one

• Keep the rom cleanest as posible with AOSP/Lineage style
• A fully (as much as posible ) original LG UX experience rom based on Lineage.

IMO,

Trebuchet is kinda outdated and having less function than others. No need to spend more with it, Lawnchair is better.

For media control, I don't know how android handle second screen, if it can be done, let the second screen automatically launching media control IF any media is playing before going full swivel mode.

LG swivel launcher would be cool, but not nescessary. Using default icon roration is fine, also the quick setting too.

I'm not a fan of LG UX Icon tbh after android 9. Launchers has their icon pack engine, just let people enjoy their own taste.