No. Pypy already does JIT. And Cython has the speed, but not the size.

The target of my phantasy compiler are microcontrollers. That's why the (correct) comment of quotemstr isn't that big of a concern to me.

Just throwing Python code at Cython doesn't really improve performance all that dramatically, because it'll be doing pretty much the same thing as the bytecode interpreter, except that all the saucy special-cases are now unrolled many times across all code.