I tend to lean towards casual exclusively, not including 1x1 arrangements. Advanced never suited my fancy, free is too fast and not to my tastes.
PM box is really the section I frequent most for anything real these days, though.
Nation was great 'till I became a total pessimist about the fact that the only roleplays I liked on there ended up dying very quickly, and the roleplays that survive tend to be ones I wouldn't be inclined to join anyways.
Arena, not to my style, same with tabletop.