This demo is awesome, adding a third dimension, a range mechanic, as well as moves and abilities that can be upgraded more than three times, even if the upgrades are usually less radical than SITTSM, they have a lot of synergies. It's overall more fun, and you were mostly right about a melting cpu.
I've had a peeve ever since the release of SITTSM. I really wish I could see what abilities, especially passive ones, and upgrades do exactly. The create-your-own-business mostly fixed the description problem a lot, (except for Saitama's passive description, wtf does that do, if anything) but now in this demo, it's difficult to remember exactly what's changing when you upgrade, and I don't think you can tell when taking an upgrade will max a move out.
I get that it's a demo, so maybe in the future there could be a table, journal, or something in the character or pause menu that shows what abilities, moves, and upgrades for those moves you've found so far, with descriptions, would help greatly. And for passive abilities, maybe u could hover over the box when you choose a character to give a description of what it does. I mean, what do "Free Lunch," "After Party," "Dead Eyed Stare" etc do? I have no idea, even though it's probably most of what separates it from the other characters