If you need more money for the Google Ads showing on your blog you need to show more ads...right? well...yes...and no. The golden Adsnese rule is to keep ads under 20% of the amount of content size you have. So if you have a long, in-depth article you should show a few more than say an article that is short and straight to the point (like this one).
As with all sites using Adsense its not about how many Ads you are showing, its more about where and what they are showing. The truth is you don't even have to create new adblocks to earn a little more! One of the easiest ways to show more or fewer ads is to go to "My ads" then select "Ad balance" and that will bring up this slider...
This slider allows you to adjust the "Ad fill rate" that Google defines as: "Ad fill rate is how often we fill available ad space on your site with ads. For example, if you choose a 70% ad fill rate it means we'll fill your ad units 70% of the time with the highest paying ads."
Please note: This is not creating more ads, its just using the existing adblocks that you have places 70-100% of the time! At the end of the day, why wouldn't you want your existing adblocks filled 100% of the time? You placed those adblocks there for a reason, not for the fun of it.
Having said that some people might resent being shown ads all the time and that is why there is a "clear area" next to a "lined-out area". The clear area is what Google has determined to give your site readers the best experience and lead to the fewer complaints to you.
The good news is you can always do some A/B testing to see how various changes to this slider are affecting your site views as well as your Google Adsense revenue. So why not set some up and try that slider on 100%, I think you might be surprised at how much extra you earn and how little people will actually moan at the extra ads.