Hi, I'm also in political philosophy. I wasn't sure about my chances so I applied to mostly MA's (Brandeis, George Mason, George Washington) and two PhDs (UVA and SUNY Binghamton). I got into Binghamton and am still waiting on UVA. My writing sample was about how Rawls' Law of Peoples could be seen as a cosmopolitan.
I chose philosophy over theory partially because of my quantitative GRE scores, I had been advised that the job market for philosophy was slightly better, plus I also heard that it's easier for philosophers to explore political science as opposed to the other way around.
Honestly, I don't know which area in philosophy is most exciting and I've been trying to catch up on the recent literature. Still, I certainly find cosmopolitan theories and international justice fascinating.