If I were your thesis supervisor I would ask you to state your aim in a much clearer way. As it is now, it is totally unclear whether it is descriptive or normative research and what kind of tools you are going to use in order to support whatever it is that you are out to test/show.
Also, if you have already decided that you are going to bring down K2, why bother to ask what people think about them?
As you yourself say, there is a lot written already about MMORPGs. If you have read some of that literature (as I am sure you have, otherwise you wouldn't be so sure of what this kind kind of research can and cannot show...), you should perhaps use it as a point of departure for your own research.
Lastly, a word of advice. There are certain people on this forum who I am sure would assist you should you ask them. There are, however, far more who would take any opportunity to flame you for reasons only known to them. Try to find out who are willing to help and you will save youself alot of time and energy.