Thanks for the suggestion. I've also been after a saner shell, and have been disappointed in one way or another with the approach of either using another language idiomatically (Python, Scheme, Haskell, Scala, etc.), since running commands, piping, etc. are all rather awkward; or using such languages with embedded shell-like libraries, which seem to have awkward edge-cases.

As a "real" shell, it looks like rc maintains the command, file and piping niceties of bash, whilst avoiding the edge-cases of shell-like embeddings.