zach, i think you've been riding the wrong fins in your singles.
Hmmmn, don't think I've ever seen a fat chick on a unicycle..............Hmmmn, don't think I wanna see a fat chick on a unicycle.
As others said there is a lot that it depends on. For me a 10" pivot covers just about all conditions.
But sometimes a fin with a nice rake is nice, or maybe the Rainbow El Gato fin can be a lot of fin. Heck I've even rode a quad set up on my favorite board it's a 4+1, but even that board I mostly ride as a single.
Grooooaann! Matt, did you have to? Pardon me while I go find some brain bleach. :-)