Have you looked at Perl 6 at all? Whitespace in regexen is insignificant if not quoted, so not only can you add a little space between sections, you can split a

Have you looked at Perl 6 at all? Whitespace in regexen is insignificant if not quoted, so not only can you add a little space between sections, you can split a regex over several lines and add comments throughout. It also has first-class grammars, so you're less tempted to reach for regex when something more powerful would help.