>>42,43
My understanding is that developers universally believe that R7RS Small is inferior to R6RS, and it seems the jury is still out on R7RS Large, but why not both, and nearly R5RS, and IEEE Scheme while you're at it?
https://www.schemeworkshop.org/2014/papers/Kato2014.pdf
https://andykeep.com/SchemeWorkshop2015/papers/sfpw1-2015-clinger.pdf