I love that idea. Yeah i know this app : it is a great example of how simple, adaptive progression can really motivate people (specially beginners).

And yes I'd absolutely be interested in discussing a UI + flow for a self-adjusting progression system like that. Yeah. Let's talk about that, drop me a DM? I can think about some (ugly) alhorithm first

I don't think they do DMs here? but anyway I posted on the Github issues with some thoughts on UI and basic sketch of data needs