I tend to prefer pea and rose comb breeds(although it makes sexing all that much harder...), which of course relates to both their looks and their cold hardiness.
I really like experimenting with fluffy faced and fluffy footed breeds(d'uccles are my favorite bantams). We have some chickens that we call our "Napoleons" because they're horribly crossbred, but originally were Cochins like my avatar whose name was Napoleon. He was our first rooster(completely accidental), and he was amazing, to say the least. So, although he's passed, we have 3 of his daughters and I think 4 granddaughters... his line has done amazing at producing hens and not a single roo since him.
I love both extremely large breeds like our brahmas, as well as our short and fat cochin crosses, and tiny little bantams. Basically, anything that's not gangly looking goes.
And lastly, I'm not going out looking for super expensive birds since I really like and prefer to crossbreed so there's no sense in spending a bunch just for the breed name.