John Shutt is author of Kernel, experimental Lisp dialect that attempts to combine fexprs with lexical scope.
http://fexpr.blogspot.com/
Do R3RS schemes with first-class environments, such as elk and umbscheme, not try to achieve something similar as kernel?
I know little about differences between various RnRS Schemes, but it appears that everyone, including Shutt, claim that fexprs are the most important issue in Kernel.