At the Against Malaria Foundation, bednet distributions will soon start in regions where AMF has not worked before: Nigeria, various DRC provinces, and one other country to be announced. If you can choose the country for your papers, probably you could help AMF by focusing on one of these?
I think AMF would be particularly interested in questions about how poverty affects bednet distribution. For example, people might have seasonal jobs, which means they regularly migrate to another part of the country. This might cause them to miss the bednet distributions in their home area, or they might not be able to take their nets with them when moving. Another important aspect is housing: do people have houses with fixed sleeping spaces and solid walls where they can hang a net?
Also, maybe check "what the hell happened to Brazil" after 2013...
or, if you want a more positive story, I'd be interested in knowing more about Botswana