I find that this comes down to design... all builds need variety of some sort to break them up, but this can be accomplished in so many ways, and they don't have to be varied blocks. I love limiting myself to, say, stones, bricks and cobble for one building, and then smooth stone, andesite and polished andesite for the one next to it; if I can keep my style the same (like they are both tutor, or modern), then I can rely on where I place blocks, stairs, slabs, etc. and keep my builds interesting but also simple... therefore I can have a town or something with a bunch of "different" buildings that are all similar style and blocks, but varied just a little. ^.^