Excellent placement! I would leave it just as is. (Is the arrow pointing downwards legal?) Also try changing your font link color to pale yellow.. so they look more like links
cool placements but not sure about the color of the title in your adsense being yellow...try making them more in the shades of blue or like your other normal links for maximum blending...
Traditionally, forum readers are less likely to click. That said, you should move the ad unit on the front page to be higher - maybe after the first post. Set it to be both text and image ads. In the comments section, you have no ads there - I would put one ad unit just before the first comment. As it is, the site is very busy looking so I'd not overload it with more ads. Try the suggestions above and see how you go.
Just something I've noticed ... if you click the arrow above your ad it hides them ... surely you don't want people to be able to hide them so easily? Put an ad after the first post in the thread.