If the Kemper Stage was crossed with the interface of the Fender Tone Master Pro, it would rule the world.

I'm sure Kemper's UI and such will continually evolve. All of the players in the game want to one-up each other in some areas to push innovation but whatever areas are less stellar, another company will likely make them their focus going forward. However, there will remain a case for users that prefer less of those features for various reasons. Simplicity's sake, less points of failure, less uncommon or not easily acquirable repair components, cost savings, etc. There will never be a perfect box for everyone though.

For me, I really enjoy the minimalism of the Player. It was a big reason why I bought it. But that's because I've had it with all the screens and stuff over the years. I don't want to create or edit on the unit. I want to play using what I already prepared while still being able to adjust basic features on the fly. The Fender does look really great but sacrificing these Kemper tones is not an option for me any time soon. But hey, ya never know what's just around the corner!

One thing that's appealing in the Fender that it supposedly has spillover between presets like the KPA. That solves one of the Helix and QC's major flaws: the need to build mammoth presets and wondering you'll fit everything you want or need in it before you run out of DSP. I'd much rather have several simpler and independent presets that I can instantly access mid song, as there's a finite number of effects I'd ever have a reason to use at the same moment in time anyway.

The other thing that only the KPA can do is hold a consistent volume when gain is changed. Nothing wastes more time in digital units than having to constantly compensate volume and wonder if presets still match in volume after I do, regardless how good the GUI is otherwise.

Perhaps the best combination for you would be to own a Player and use it in one of the Fender's loops? This way you'd have all that you like about the KPA to use inside GUI of the Fender that you like. This would also solve the volume balance issue I described. For me, when I'm messing with amp tone, I'm messing with amp tone and not focused on other effects. When I'm building whole rigs and performances with various combinations of effects, my starting point is to select an amp/cab profile or set of amp/cab profiles that I've previously chosen from many others, and tweaked to taste. The only change to the amp I'm making at that point is maybe lowering or raising the gain a tad.

It already RULES!

... it certainly rules already here with my Power Kabinet!

I personally would much prefer the stage with a more functional iOS app, better in every way even in the studio so you can keep the stage where it belongs on the floor. Add a power Kab for the most versatile and portable rig.