Since most of these notes can be taken as criticisms of Scheme, I assert from the beginning that Scheme is my favorite language. Few other languages are worth complaining about. There will be few concrete suggestions for improvement in Scheme, but here are the itches that irritate me. Few are fixed in any language.

Keykos Factory
Notes on Scheme and Sensory Data Access
Problems with Scheme
Efficient Synergy
A worry about eval

Other Scheme notes