Arthur should chime in as the SRFI editor and suggest a standardized
layout for SRFI repos :) As it stands, the improvised layouts make them
hard to navigate unless one is already familiar with a particular repo.
The convention of having a srfi/ subdirectory has begun to take hold, but it isn't uniform yet. I'm still waiting to see. And given that different Scheme implementations use different structures, I don't want to do something that isn't convenient for the SRFI author.
However, the convention that I am trying to enforce on new SRFIs is that SRFI implementations appear only in their own repos, leaving dependencies that are other SRFIs in their own repos. Duplication for the purpose of making finding dependencies convenient has been a nuisance when updates are made to the implementation.