I've only had my Kemper Stage for a week (and I love it), but here are things I would like to see:
1. Keep knobs and buttons. I don't want a full touchscreen like a QC, but a better UI would be nice.
2. Add an on-board rhythm machine and/or metronome
3. Add an audio in (plug, or bluetooth) for playing along with backing tracks, YouTube, etc.
4. Ability to run two profiles at once (in parallel).
5. Ability to have all post cabinet effects in parallel and Kill-dry, for a true Wet-Dry-Wet configuration.
6. TC Electronic 2290 and 1210 models (along with some other iconic rack gear like Lexicon PCM series).
7. Ditch the USB A and B ports for USB C