Hi. Last minute comments:
In the rationale section: This version no longer contains procedures from Gauche's data.random, I think.
If it's correct, you can drop the reference to it.
make-iota-generator and make-range-generator: It may be obvious, but maybe helpful to explicitly tell
the conditions that returned numbers becomes inexact, e.g. "If both start and step are exact, it generates
exact numbers; otherwise it generates inexact numbers. The exactness of count/end doesn't affect the
exactness of the results."
(The last condition is useful to give +inf.0 for count/end)
About Authors: Originally I saw text lifted from Gauche manual, but now they are mostly rewritten
by John. It's up to John, but I'm ok about any order of authors.