It will be a challenge to make an interpreter for a better language faster than dead slow.
I would bet on a compiler for a better language instead. That way, only one person would have to wait ages and ages. I doubt the result would be fast, but it wouldn't be insanely, insanely, insanely slow, either.
I would much rather hand assemble machine code than program in sed. I imagine most people have a better understanding of how computer architecture works than how to do arithmetic and logic with sed.
We started with nothing, remember? Just the bare metal. If this were the only available programming, I'd write an interpreter for a better language.
Never imagine that your current suite of tools is all there is.