So this is neat. I like the idea of giving viewers a chance to experiment without needing to make their own game and levels first. I took note of a few issues that I think could be improved.
First, some potentially bugs:
- Jumping into a platform puts you in a grounded state, even if you continue to travel up. They seem to try to push you to the top of them when normally they should act like a normal tile but only when you are entirely above them. (your collider bottom is above the platform's collider top)
- Jumping into a corner with the rounded corners option on gets you sort of stuck. I assume this Unity's collision system at work which you should really try to avoid as much as possible when focusing on precise movement, at least in my opinion.
Some other more game-feel stuff:
- The base movement speed is too high. The slider would lead people to believe they need to set it to a point faster than most plaformers have. Those that do let you run really fast typically have a dedicated run button so you can be more precise when you need. The levels are also not really built for that amount of speed. I settled at a speed of 8, which felt fine, though tbf I am more used to action platformers like Hollow Knight and Dead Cells.
- Speaking of, the numbers you use for the sliders don't make any sense. If I wanted to actually import these into a game, I wouldn't be able to. A standard unit like pixels and frames would be nice. Edit: I see a lot of comments suggesting an import/export feature for the stats. I wouldn't necessarily recommend it since it doesn't help anyone not using Unity. It also doesn't teach people how to implement it on their own, so they'd have to come back to this every time they want to change something.
- This one's a bit personal, but I put a lot of attention into how short hops feel in my games. I like when it's not visually obvious when I release the button, but in this game it is. It mainly comes down to the exact math that goes into how jumping works, and again, personal preference.
- I think air brake and air control could be the same variable. (aka Air Acceleration) The whole point is how well you can change your momentum in the air. Both variables accomplish that in different ways, but they also heavily rely on eachother. For example, if I turn air control all the way up and air brake all the way down, the air control has no affect at all. A single air acceleration stat would also be easier to understand for people who aren't used to complex physics engines.
- The ignore jumps camera setting just looks awful. I get the idea, but you shouldn't make such drastic camera movements or it's easy to lose your character. It also struggles with the aforementioned platform issues.
- You can't close the toolkit while the narrator is talking.
- Maybe this was outside the scope of the project, but I was hoping to see the dialog react to my settings. Instead, they give generic information on how the stats work AFTER I've been given the chance to figure it out myself.
Overall, I think this sort of thing has potential. It just needs some work. I will say, I find it weird that this was inspired by the Celeste video where they stated they used XNA specifically to improve their movement, and then you used Unity for this anyway. It was probably the better call for familiarity and so you could use webGL, but when I can clearly see some stock Unity problems like the rounded colliders, it does hurt a bit.
I could nitpick more, but these are what I found most obvious and/or most counterintuitive to the idea this is going for. If you can clear some of these up, I think you're good to go, and I would love to see this sort of thing expanded upon.