It'd certainly be interesting to write a C compiler codegen target for the 6502 that treated the zero-page as registers (and a lot easier to map modern compiler intrinsics to than the tiny base register set.)
Some years ago I worked on a C compiler for a processor, which, like the 6502, had no general-purpose registers and a ‘fast page’, and we did exactly that.
Chances are, someone is already working on an implementation.