I know I'm not going to escape all the drudgery in developing my tests. But I have an extreme case of Laziness, and I'd like to duck as much of the drudge as I can. Also I'd like to build on others' work in case I come up with something useful enough to share. That way I don't have to maintain the whole pile myself. (More Laziness. At least I'm consistent. 8)
I believe that Test::WWW::Mechanize is still a work in progress. You could always msg petdance (the author of both WWW::Mechanize and Test::WWW::Mechanize) and see if he is interested in any of your ideas on how to make it more useful.