The key to good worldbuilding is leaving out most of what you create. You, as the author, had damn well better know the where all that dragon food comes from, but that doesn't mean that I, as a reader, want to read a five thousand word essay about you explaining it to me. I don't need to see the math, but I can tell by the details you provide whether or not you've thought these things through to their logical conclusions.
Patrick RothfussDon't get me wrong, hard and soft fantasy stories can both be good. But you need to know which camp you're in. I'm into realism. I'm a hard fantasy guy.
Patrick RothfussI want a magical horse that fits in my pocket," Wil said. "And a ring of red amber that gives me power over demons. And an endless supply of cake.
Patrick Rothfuss