Will involve a lot of playing around (multiple uploads of the css file) to get it looking right, so it'll be easier just to do it myself. Either that or I setup a local copy to tinker with and give you the finished product but honestly that's a pita.
So, it seems to me that everything is too monochrome. There's nothing to draw your eye to any of the elements which need your eye drawing to (I'm lookin at you, new post indicator).
The code itself is fine, it's random things that haven't been formatted that is the pain. If you spot anything that looks obviously out of place let me know.
I would like to comment that if the discussion is closed, it shouldn't stand out super loud like it does now. I'm sure you're on that already, but just thought I'd mention it.