Thank you so, so much for your detailed suggestions! I do have a topic - it is broadly speaking infertility and the rise of the treatment centers in Kunming... in certain areas of town it seems like you can barely walk 10 minutes without seeing ads. I wanted to look at it in the context of the controlled births policy and how it has opened up, but seeing as it is already a sensitive enough topic avoiding the political sounds like a good suggestion.
I also really like the idea of focusing in on an ethnic group - it is an idea I've been playing around with for a while, especially as a hospital based ethnography looks more and more unlikely and anthropologists here seem to favor village-based ethnographies. Unfortunately I can't be too casual about data collection - my college's IRB requires consent forms and institutional permission and such, though I am talking to them to see if they will at least let me take oral consent instead of written consent - there seems to be an aversion to signing unknown forms!
Thanks so much again - and the bit about being an anthropologist didn't sound pejorative at all - that does seem to be a big part of the game :)