Yes, that sucks... so does lack of control over stroke/shadow colour and positioning... imagine the cool glowing interfaces you could dream up if you could control these elements as well.

Really, no matter what you want to do with OS X it's a compromise... pure design is impossible really (and we'll probably never have Kaleidoscope-level control over the interface), so anything you do has to fit into this very limited framework. It's sad that from a customization standpoint PCs are now light years ahead of the Mac. But I'd rather use a Mac stuck with Aqua than a PC tricked out with a wicked interface overlay, anyways - beauty is more than skin deep in this case.