Hello 10w73,
I see that you are playing a 2014 Gibson Melodymaker among others!? I have a 2015 Les Paul special doublecut, (obvious) with the same p90s.
I play my Kemper with custom made UE InEars too. With my Gibson I had similar difficulties to find a good sound, until I changed the P90s with a pair of Pickups from Bare Knuckles. (In my case, the „supermassive“, a more modern sounding pair).
What a difference it is! The guitar now sounds „right“ with the same kind of rigs, without much tweaking.
Maybe that‘s another point to think about?
Regards
Dirk