Which is funny, I thought the #! theme I made was way too dark and quit using it. 
I also tried cribbing the colors from the Windows XP Rainy Day scheme and also my wife's Mac OS X 10.5 machine and came up with a few different schemes. I think I also came up with an all-gray flwm-esque theme, but I didn't save it. The Mac scheme seems to make me happiest.
But yes, the default JWM colors are pretty corporate, which is awful to many.
VectorLinux Light uses JWM as an option next to IceWM, that's how I found out about it. I borked that install by installing a bunch of Slackware updates on top of it... oops. So much for slackware compatibility. Next time, I'll use Salix instead when I dare to stray from Debian. That repository is just soo... addictive. 
I am having vague thoughts of rolling a JWM-based Debian distro. Not that I have the time, with a real job, a family, and a raging addiction to cycling.
--Ben