Contrary to popular belief, one of the aspects of the guitar signal chain that dictates your guitar tone in a major way-is your Cab/Speaker choice and mic placement when capturing that tone or the Impulse Response being used.
One of the consistent things among the Neural DSP plugins is the IRs that Nolly Getgood does. I think what you're liking the most about the tones you're getting is due to that.
I've actually disabled the cab section and used the same IRs when comparing Kemper Profiles and the Neural DSP plugins, and the result was just really unnaturally tight bass/low end and a lot of high end content with the Neural DSP plugins in comparison to Kemper Profiles (when comparing just profiles and the amps from the plugins with no EQ and without any low or high cuts on with either)
Before selling your KPA, maybe try just using the Cab section of the Neural DSP plugins along with the Amp section of your fav profiles and see how you like the results.
If you like those results, then you'd probably be just as happy with investing in GGD ZIlla Cabs Studio or the ML Sound Labs Mikko Cab plugin. The GGD Zilla Cabs Studio is an entire library of IRs made by Nolly Getgood made with different speakers and taken with different mics, and you can mix the IRs in a really easy to use interface in order to create your own custom IR's with Nolly's library of IRs. Definitely something to look into as an alternative if it really is the IRs that are the make or break factor in the tones you like.
It's definitely something to look into! Because your KPA unit is capable of so much in comparison to a plugin, its worth putting in some time to see if you can figure out what you can do to get tones you want out of the unit imo. I think if you sold it and went with plugins, they'd leave you wanting more out of them in some situations and you'll probably have to compensate for that with other gear. Just consider how many high quality effects and stuff like that the KPA has in it and compare to the basic few pedals in each plugin and going with the choice with more options usually gives you more versatility in some situations. But I think that's why you're asking for the community to help you see more perspectives on the situation and kudos to you for that my brother. We can learn a lot from different perspectives and I hope some of what I said can help at least a little bit lol