I preferred eureka as well... when it was current, I'd play eureka more than the rest of the game! It was fun, had a sense of community and you could make so, so much money!
I absolutely hated the southern front. However I like zadnor. I think it's beautiful even, maybe because of the open sky. But yeah, zones in eureka were even more beautiful than that! (I personally don't like how hydatos look, to me it was the blandest one).