Smaller icons, most notably the forum icons:
http://www.toyotadiesel.com/forums/t...m_old_lock.gif
Would look a lot better. Looking good so far though man, I dig the colors as they are, just need to mix it up a bit with the buttons, as you've said.
Look in the styles section and try pulling the images out of one of the already released styles if you're looking for some dark ones. There are quite a few in there.