Winter areas and deserts are my favorites. I especially like Reapers march, which is a high desert.
For me so far its Stonefalls that is the worst. I am in it for Cadwell's silver. Its like a kid with a bag full of a plastic toys with scenery items (trees, hills, buildings, etc) dumped it all on the floor in the middle of a food coloring and baking soda fake lava school project.
But I guess that would be artwork too. Every alliance seems to have 1 zone that is not as nice as the others, but maybe that is planned.