I did geog and fm at a-level too! I don't really see people that do both of them that often. I totally crammed case study info before the exams but I realised as long as you get the arguments from the case studies through, you don't need to memorise too much, just some key details like dates, stats etc. I used to write every single case study for each topic onto one side of A4 so I could look at all of them at once and compare the differences.
Although I never really lost my interest in geography after all that (it's one of the subjects in my joint degree at uni), I totally relate to the essay writing... even at uni now I can never think of enough points and explain them for an essay... I take forever to write like 500 words. Sigh. Something must have possessed me in the A-level exams to write so much for 33 markers.