I am new to CSS things but going through some general threads regarding subject selection, I finally opted for these:

1)IR (preferred over Pol Science as it covers parts Current Affairs, shorter comparatively and more of opinion based rather than cramming)

2)Criminology (favored over International Law on grounds high scoring, shorter outline)

3)Environmental Science (over Gender Studies though comparatively lengthy course outline but it will cover part of General Science)

4)US History (albeit I am comfortable in all streams of History subjects but opted for US history as of shorter course outline considered European, Indo-Pak History, and Islamic History too, dropped former being lengthy and later two being prejudices in them)

5)Anthropology (high scoring, narrow outline in comparison to Sociology)

I have opted for these subjects after considering past papers of previous 3 years besides taking care of course outline for each, suggestions welcomed.