In my experience the Cab Clone itself did't matched the tone of the amp.
The UA Apollo Twin with UA 610 plugin helped so much in compensating the low quality of the cab clone.
So my routing was:
- Guitar > IN Kemper > Direct out > Amp
- Cab Clone (Amp) > UA Apollo Twin > (UA 610 plugin) > UA Line OUT > Return Kemper
Thanks for sharing your way of working. Did you use the preamp on your UA Apollo or the Line in?
I'm thinking to try a passive DI-box, and profile only the amp (no speakers) and then use Cab IR, such as ML Mikko Soundlab, Wall of sound etc.