My answer is a lot like Amanda's. The preview is what draws me in. I am always looking for things that I don't have. I don't like cutsey wootsy stuff either, I dont know if that is because I like to Art Journal too and I prefer to be a bit grungy when I do that but I stay away from kits that are too pastel and have little animals and stuff like that.
I also prefer specific designers. I have three or four that I have just about everything they have in their stores (much to my husband's displeasure!) I've gotten so that when GDS puts out their collabs I can usually tell who did what elements or papers!
I too would rather have more elements as many times papers go unused for me...although I am trying to use each kit more.