Couple of points from me:
1) You are not an irritation, we have all been through periods of finding the right set up so we all understand your pain
2) There is NO perfect monitor solution, only what is best for you. And I mean this for all solutions, not just the KPA. Guitar cabs have massive impact on the sound, so every monitor solution you try, you almost have to start again
3) Not everyone loves the Kabinet. I do like mine BUT I also don't think about it too much as its mainly just for me to hear, I care more about the FOH sound. Also, increasingly I'm using it less and less because I'm tending to use the in house monitors, making it redundant
4) I think there is an element of this being in your head. I've often seen people get an amazing sound out of gear and then I play it and...oh, where did it go. The old addage of sound being in your fingers is true but I also think we hear other people different to ourselves. I'm convinced my sound isn't that great but so many people have told me it is. I even check with sound engineers at gigs and they say its great, so there is an element I suspect where you sound better than you think you do. I go round this cycle of " this sounds different to how I remember when I played it last week"...of course it doesn't but my head tells me something isn't quite right...
Feel for you dude!