I'll take the more impartial approach:
Firstly, you say that gaming uses 5-10% of your battery life, after what time? Ten minutes? An hour? And how long is your phone lasting during the day, and doing what, for how long? If you are constantly streaming Flash content on a weaker 3G signal, and it lasts only a few hours, you can hardly be surprised. I am a heavy user, but I get enough to last me through the day with 30% left on my DHD, which has worse battery life than your SGS2.
Secondly, if you wanted specific apps and games, you should have researched before you bought. Android apps aren't bad (certainly none of the ones I am using), though I will say that it generally takes a bit more searching.
Finally, if your phone is getting that hot, there is something wrong with your phone.
Before making any moves, try a reinstall, then a replacement if battery life and heat are a major issue (ie. really hot), then consider moving. However, an iPhone 4 isn't a great buy right now, with the iPhone 5 just round the corner.