The mail list discussion has died down, so I made a start on updating
SRFI 179 in a series of commits here:

https://github.com/gambiteer/srfi-179-followup/

I have tried to address all the issues that Alex raised, as I understand
them, except for renaming array-elements-in-order?.  Perhaps the name is
unfortunate enough to require change, that's to decide for later.

Here are the list of changes to SRFI 179:

     specialized-array-default-safe? and
specialized-array-default-mutable? are now SRFI 39 parameters.
     array-copy no longer allows changing the domain of the result, use
(array-reshape (array-copy ...) new-domain) instead.
     make-specialized-array now accepts an optional initial value with
which to fill the new array.
     The SRFI 179 procedures array-fold and array-fold-right have been
replaced by array-foldl and array-foldr, which follow the definition of
the left and right folds in Ocaml and Haskell. The left folds of Ocaml
and Haskell differ from the (left) fold of SRFI 1, so array-foldl from
this SRFI has different semantics to array-fold from SRFI 179.

If any of you have array algorithms you'd like to have implemented in
this library, I'll be happy to work with you to see if it works OK.

Brad