i don't pretend to be any expert, but i've been running adsense on my blog for a while with simply text links at the top. I tend to get about 10 clicks per day with 200 visits. Your placements look good to me, the main thing is to keep them above the fold. I would certainly put one at the top. Perhaps you could experiment with blend-in text styles to see which one is best. Otherwise, pretty good. Not too many ads, and not too few.
I was looking for the typical text adsense and was wondering where you ads were! I agree, I would push you ads a little higher up the page - you are limiting your reach to only the people who scroll down.
everything looks perfect to me but try to put one adsens unit below every title it generates lots of money ,believe me