This looks exactly what I'm trying to do with SPy -- although SPy is still "not there" and it's WIP. I literally wrote an intro post about it yesterday: https://antocuni.eu/2025/10/29/inside-spy-part-1-motivations...
One question, more out of curiosity than any genuine need: do you (or do you plan to) support any kind of trait/interface based polymorphism? E.g. it's a pretty common idiom to have a function that works on "any iterable type" and that sort of thing, which seems like it would be best modeled as an interface. I guess you could argue that's at odds with Python's tradition of "duck typing" but then again, so is static typing in general so I'm not sure.
I only wish discussions happened elsewhere than Discord, e.g. Zulip, where you can have web-public channels, which is great for searchable documentation, and you can interact with channels by email if you so desire.