Hell, I'm a straight woman, and I think NextDoorNikkie is fuckable.
Princess BlueYez is my personal favorite though.
Not so long ago I hooked up with a guy who was starting a non nude site. Took me awhile to figure out the appeal of them, as they are clothed, and scads of chicks are taking it off.
But it all lies in the 'less is more' concept...the tease...and the relationship with the individual girl.
As to what to do with them, it helps if the photog goes for the niche inside of the niche, like GG said. Phil Flash seems to be good at that.