The problem is, those categories aren't wholly representative of the devices. Resolution and PPI (which are dependent) aren't the only things that matter for a screen. Colors, viewing angles, and such also matter. You say OLED screens are overcontrasted and have artificial colors? Yes, but believe it or not, a lot of people prefer more vivid colors and richer blacks compared to more natural ones. Also, do you expect the same degree of reality out of everything that you own? If not, then why specifically colors on your cell phone? Besides thinking that it looks better of course.
The iPhone does have a better GPU, correct. But the S2 has a faster CPU, clocked at 1GHz. Also, which benchmarks are you citing? If you're using the Anandtech ones, note that they did everything with stock phones right out of the box. But notice, the point of going with Android is the freedom to change your browser and bootloader. That's, I dare say, the point of Android. It gives you more customization with your OS. You might say that out of the box, the 4S does better on benchmarks than the S2, which may or may not be true, but the people who want a phone that is optimized to a standard would not choose an Android phone to begin with.
Videos goes in favor of S2 considering the 2 MP front facing camera vs. the 4S's VGA. For pictures,
there are pros and cons to each.
Regarding security, it's like choosing between Windows and Mac. Yes, iOS is more secure, but it also limits you in what you can do. The tradeoff is between security and customization/freedom to do whatever you want to your phone, thus listing the category that is skewed towards the 4S but not the one towards the S2 is an unfair representation IMO.
True about games and accessories, although more games are free in the Android Marketplace. Some people would rather have ads in apps rather than pay for them.