For me personally, I like medieval themed building. The Natural texture Pack was a great step forward. The Skyrim Mashup was a little too much and not much fun in survival. The Fantasy texture Pack is completely wrong unless you like old 8 bit rpgs.
I think it would be interesting if they choose a genre, like Modern, Medieval, Realistic etc. setup a quick and dirty website and allowed users to vote on what each texture was, maybe give two or three choices for each major texture. Or even better, they really wouldn't even need to add any, just let us choose from the existing textures for each item.
Aside for the hassle of setting up polling and keeping it honest, it couldn't cost that much money to setup and would gives us a good chance to feel like we have a little power and let them know what we want. I am sure the revenue from sales would cover that part.
Call it Builder Choice Texture Pack #X and have fun.