After my pathetic attempt of a research I have decided to follow Egoraptor's advice and look at other games to find out what makes them good, or why people appreciate them.
The most interesting kind of games to research (in my opinion) are flash games. They are produced within only a few months and are very fashion sensitive. For example tower defence games were really popular a few months ago, but now physics-based games seem to most popular.
Finding a good flash game to review isn't that hard, I get a Newgrounds top 5 of the previous day's submissions in my inbox every morning. Every Monday I shall write a review about the highest rated game in that list concentrated on why they are liked that much.
My latest Monday's "Daily Best" Review (MDBR) is about The Great Siege! You can read it here: link ^^
The other reviews can be found here: Another Link ^^
Don't get disappointed because there are only 3 reviews yet, I will write one every monday!