just a remark (already observed in previous much older version): during AA session in car, I am used to have phone calls. When calling, current streaming automatically switches to PIP mode and that's ok. But, after 30-60 seconds and during the call, the data connection is lost and whatsever APP gets closed due to missing mobile connectivity.
I don't know for what you need it, but you could try to use the phone without any modification from any Magisk or Xposed modules to see if it's better.
The A2N kernel goes better with the Stock Rom, but the nice thing is that everyone can adjust it depending on what they want, performance or battery.I was using this kernel with stock ROM and I'm trying hades q now. According to my experiences this kernel is better than hades for battery drain. It depends many thinks. There is not a best kernel or ROM. Which one is good for you, just use it. But pls don't blame on devs. If you find any bugs, report them. They need support.