Diamo - it was easy to reproduce the problems you were having. And yes, your Telecaster demo is a big step in the right direction. A general rule of amps is that dirty amps work better with pickups that sound midrangey, barky even - rather than full and sparkly in the clean guitar sense. There's a huge pickup and overdrive pedal industry that caters to this, and in regards to taming nasty, scritchy fizziness that too is a skill to be mastered.
Recommend starting with Glenn Fricker's channel on YouTube if you're starting from scratch and expand from there (Mixerman's books, Andy Sneap's forums, Rick Beato's channel etc.) - dirty guitars are a big subject.
Dude, this is really really helpful and encouraging to hear.
If I can take more of your time. I have a couple of questions for you.
1. Does the 'Go Jimi Go' sound pretty awful to your ears in both the S Series and Telecaster recording I have done?
2. Does that profile sound good on your setup?
However, I feel all of the profiles sound very 'square wavey' rather than 'saturated', I don't know how else to put it. Do you really think that it's a matter of my US Tele and S Series not having sufficient tone in them to get a good sound out of them?
I'm feeling pretty skeptical of the Kemper's capabilities because it sounds like there is a fundamentally sort of flat, buzzing quality to the tone it produces. But then I go and listen to demos and it sounds lively, bright, chunky, fat, detailed etc. My Tele sounded awesome through my old Mesa combo, it seems bizarre to me that this (and my S Series) is not good enough to get at least into the same ballpark as the demos I hear online. Do you agree my tones are pretty garbage?
Sorry for ranting a little but I feel a need a massive sanity check after getting lost in the wilderness for so long... I don't trust my ears any more!