My Issues with BOARDS
First, GD wasn't broken so I don't even know why you're trying to "fix" it. With that out of the way, my issues:
-Dark green on Darker green on a Darker black background with a very similar blue-ish green streak - hard on the eyes.
-Proportionally large images on thread title lines: This is what kills it for me. It creates a cluttered, disjointed look
I really just liked the plain old GD forums.