May I offer a word of caution at this point?
It seems like you have already spent, and continue spending a lot of time on this issue.
If you are genuinely enjoying the process, please keep going!
Otherwise, you may consider switching the Kemper for an amp sim in your DAW, a modeling amp or a "real" amp for a couple of weeks. Or just play and/or record some acoustic guitar?
This might help you get your ears and brain get "unstuck" from the frequencies that bother you with the Kemper now. Or maybe even alert you to the fact that the same frequencies are present in real amps and amp simulations as well.
A lot of times, what seems to be very unpleasant parts of the guitar tone on its own, helps it to sound really good when mixed with other instruments. A lot of Kemper Profiles, especially professional ones done by recording engineers, are not meant to be listened to on their own, but in a band context!
And if unpleasant frequencies don't help, they are routinely EQ'ed out of the guitar signal in the mixing stage.