You can see the different models in action here pretty well. The Mini seems to be using older gen hardware so it sounds worse than the Ampero II Stomp/Stage.
While the Stomp/Stage could use at least one more encoder, I think they've done a good job with what they've got.
The cursor thing seems to be only on the Stage so maybe these are on different firmware versions. In any case it works exactly like operating a touchscreen UI on most things and the cursor is only to highlight things you clicked. I guess the menu/value knob is just an alternative way to move the cursor around if you prefer that. I like alternatives rather than locking you to a single paradigm.
It's also clear they've tried to alter the UI a bit to fit each device. The Stomp/Stage don't have those +/- buttons of the Mini because you have the encoders for that. There's also plenty of thoughtful little touches like very fast access to overall volume control (touch the left knob to pop up output levels) or toggling between scene/stomp modes. That's nice attention to detail.
They've also thought a bit about parameter order where e.g Amp is Gain-Presence-Master --> Bass-Middle-Treble which works in an intuitive manner for commonly adjusted together things. Both Fractal and Line6 could take notes from these because their onboard UI parameter order is often not intuitive for "what is adjusted together most often" and thus requires extra paging. Line6 especially buries its Mix parameter way deeper than it should be and Fractal requires a good bit of back and forth on some blocks because e.g Amp gain vs master/level, or 3-band EQ vs presence/depth on different rows.
I'm not saying it's some pinnacle of UI design, but it seems fairly straightforward and easy to use without too many "how do I do this again? where was that thing?" pitfalls or too nested navigation.
These are 466 and 699 €. For comparison, you can get the Stage for the price of a HX Stomp and a FM3 is double the Stage's price in Europe. Sure, the sounds aren't exactly at the level of the gear we usually discuss here, but for the money, pretty good.
@GuitarJon certainly gets good tones out of the Stage. I don't think any of us here are jumping to swap their Helixes, Fractals or QCs to these but for players with less money, pretty easy to recommend over the "Slap your own label on it" gear at the budget end.
Our favorite modeling companies have just put the bar very high for amp/fx quality and without capturing I don't think it's easy for any smaller company to compete, when even Fender is not at the Line6 or Fractal level.