Each web page should support displaying 3 banners/ads (With Google adsense up to 3 ads can be displayed). Right now some pages like home page can display only one banner and some pages like Search don't even display any banner. This becomes very difficult to earn money if your site doesn't charge any monthly fees and is dependant on banners/ads only for making money.
Additionally, the pages should support most commonly used ad formats suggested by Google i.e. 336x280 Large Rectangle, the 300x250 Medium Rectangle, and the 160x600 Wide Skyscraper.