The power amp in the Powered Kab is an ICEPower 300ASC, it is rated for 300W @ 4 ohms. The Neo Kone in the Powered Kab is rated at 200W and 4 ohms. IMHO this is perhaps plenty of amp you might expect to need with the Neo Kone in the powered Kab. It should get pretty darn loud, and if everything is set and plugged in correctly and the Kab is working correctly, you might just need more Kabs as a single one just won't get loud enough (it is a single 1X12 after all).
I dimly recall a way to set the maximum power out of a powered Kemper head in the settings, having that set too low would reduce max volume of an unpowered Kab. Is there a similar power limit setting for a powered Kab in the Kemper?
To the OP; when you are running out of volume with the powered Kab, did you happen to notice how much power was indicated on the power meter in the Output block, and was the volume set on the Kab where it needs to be for the power meter to measure accurately? IIRC you have to have the volume on the Kab itself all the way up for the power meter in the Kemper to read accurately.
Thank you. all great advice which I have, since first posting, uncovered some of it, I would suggest that Kemper give some sort of heads up with the packaging regarding all these factors or even just a couple of the more important bullet points. I sincerely appreciate you taking the time to give me advice. That was very generous and kind. Thanks Mate!