Two things about a Master's thesis:
- PROCESS of picking the thesis subject..
- The actual research, experimentation, collection of results, data handling and synthesis, and writing the 'paper'.
In my opinion, you should not hurry part 1. If you find a subject that approaches the state of the art, presents some important question, takes more than reading to research, and results in some fairly unique insight or application, you will find all that stuff in part 2 will fall together, point you in the directions you need to go, and actually be enjoyable.
Also, be aware that a Master's Thesis is (supposedly) practice for the PHD Thesis. I don't agree with that, but you should make sure you understand your school's perspective on that. Legend has it that at overachiever schools like MIT, the Masters Theses are better than the PHD theses. I don't know.
Personally, I would want to make sure that the time spent on this resulted in my learning something that I thought was really worthwhile. Not just RequiredBS.
I am not a good example of any of this. I have a very "Mongrel" academic background. At IBM I was was asked to do "Career Day" programs for High School students. I had fun doing that, showing cool stuff to do and learn, but I had to warn the organizers, "Don't ask about my Academic Background!".
Maybe look at: Graduate Students
Let us know how all this works out.