There should be more, and also research on the regional disparity, also from social sciences, economics...
How come network operators in the US have more address space available than in other regions? How does this influence their management strategies and what technology they deploy? Should addresses be redistributed? If so, how?
Could large-scale Carrier Grade NATs influence user experience in practice, e.g., your ISP selling you "Internet" limited to 256 concurrent sessions?

Anyone? :D