Hi, I've done quite a few experiments with Blogger ad placements and I'd like to share my results. I hope they are useful to you. I operate over 60 different blogspot blogs besides my websites, and these tips took my blogs from 2% CTR to 15% CTR on entertainment based sites, and over 20% on medical sites. 1. Use the Minima Lefty template. This is the simplest template and it also gives the best opportunity for ad placement. 2. Place 2 336x280 ads in your top center column, and one 160x600 ad in your left column. 3. Place an abbreviated blog roll of around 8 links at the top of the left column, just above your 160x600 ad. This will stagger the ad just a bit which will help reduce ad blindness. 4. Keep the standard blended adsense colors, except change the title color from gray to black. This will make the ads stand out more to your viewers. 5. Change your navbar to black. It blends in better with the template. This may not be the absolute best way of optimizing your blog but it's the best I've come across, and I hope it helps you too. I've created an example blog for you to see what it looks like, here: http://adsense-example.blogspot.com/
right well the question is whether you want to inflict all those ads on your visitors. for me, this is a job rather then a hobby, and i like to do whatever i can to gain revenue, as long as it's ethical and isn't something that i'd personally hate if i were a visitor.