Tweaks that work? (yes very subjective topic)

No amount of tweaking will replace playing your table thru the best phonostage you can afford.

I didn’t see a phonostage listed? Mandatory, before obsessing over obsession.

Edit-your profile list the Moon 110-up your game with the phonostage. If you haven't heard a nicer phonostage in your setup,  start demoing to hear what the fuss is all about.

   "the phono stage is in the 390 and it is the 310LP"

internal phonostage? You may be surprised how an outboard unit can be a game changer. Your setup appears solid, but that is where I would look for possible, significant improvements. 

From the audiogeek perspective, that is the compromise-internal phonostage. I would be steering my time and wallet towards a separate box. Try and demo things to see if your ears agree. Ever hear a tube unit thru your system? Could possibly add some "life" you didn't know was missing. Personally, I lean toward all tube setups.

Records and tubes are what create "that sound" I constantly chase after.

Subjective, of course. There are plenty of tube vs SS threads that go nowhere.

If that were my setup-better phonostage which will eventually show off an Apheta cart. Now you're done, until you get the P10.