Honestly, I just want a hard fork of CPython with a few different design decisions and cleaning up of stdlib to support them:

* Attributes are no longer dynamic, __slots__-like behavior for everything by default

* GIL no more

* Base off of Pypy for JIT speed

* Real lambdas (I like how Lobster does this)

* Maybe make type annotations required (but with inference)

Python's syntax is so close to nearly perfect (if you don't mind tab-delimited code, I've gotten used to it)

I think it would go over better than people fear. If you do what you can to make the core language fast enough, C extension stop being as relevant. Right now, the Python ecosystem is absolutely held back by the FFI hell that it's stuck in.