Beorn-eL-Feared
Idiot riding pedals
lurker's comment: Of course, with limited cities, you want to make the most of every square in your territory, and avoid nuisance overlaps. However I wouldn't overlook the fact that, even then, you'll only need 13 workable tiles per city, which means every one of them can spare 8 of its natural fat X to the others through overlap. My focus would certainly be on getting the most out of hills, BG and FP tiles, which provide a little plus when compared to those standard grass, plains and desert tiles for which you will lose nothing when settling on.