It's been pointed out to me the eq- and eqv-comparators aren't as useful as they might be because they mandate default comparators.  I would like to change this by inserting the following language from SRFI 125 into SRFI 128 as a post-finalization note:

Implementations are permitted to ignore user-specified hash functions in certain circumstances. Specifically, if the equality predicate, whether passed as part of a comparator or explicitly, is more fine-grained (in the sense of R7RS-small section 6.1) than equal?, the implementation is free — indeed, is encouraged — to ignore the user-specified hash function and use something implementation-dependent. 

Comments?