It would be nice to make the wp_list_pages() query filterable so, for instance, I can filter based on post meta or other args.
I tried to follow your style so the wp_parse_args got bundled in with the trim on line 637. Could split it out as its own line if you favor readability over succinctness.
Make wp_list_pages query filterable.
Make wp_list_pages() defaults filterable. Skip wp_parse_args().
Take a look at 94104d5
Make the wp_list_pages() query filterable. fixes #2