Tweaking is a big trap with any digital gear.
Personally I find I don't do any tweaking with the Kemper, I browse a few rigs till i find a sound that inspires me, and love this aspect of the unit, but otherwise all I tweak are my fingers. I know tweaking wont fix the problems in my hands.
But it's not for everyone. If you have a grailtone in your head it can be hard to avoid trying to get there with artifice. With the Kemper it helps if you've profiled your own amps, then you can let go and realize, that every single profile is actually good and useable and is an authentic recording of that amp in that room with that setup, and you can get past the "it's digital" concept in your head. It also makes a huge difference how you monitor. If you used headphones or poor speakers at low volumes, then go play a valve amp maybe even through a 4x4 at stage volume, the real amp is going to win out every time, it will sound richer, bigger, more complex, simply because it's louder and the frequency response is more natural. Monitor through good speakers at a decent volume though and the Kemper will be just as good and often better. It all depends what you're looking for.
Anyhow, good luck with your continued search for the right kit!