You admittedly made me change my mind a bit about Vala. Apparently it was ahead of it's time, which is a bit sad. Nevertheless, elementary is the closest thing I know to a working open-source desktop OS, and Vala hinders it's adoption.

At some point you gotta pick the hill you're gonna die on, and that shouldn't be dev mind-share.

The horse they bet on didn't make it, why fall into the sunken cost trap, either bet on a different horse (rust), or pick a tried and true one (C) and write a decent FFI for alternative languages.