War World's obvious resemblance to the Death Star didn't irk me. You know, sometimes when you make a nod that's so obvious, it actually puts a smile on my face instead of making me rage, "WHAT A RIPOFF!!!!" It's like the artist says, "I'm a fan, I know you're a fan, so enjoy the reference!" An example when I think an obvious nod works well is the video game Revenge of Shinobi.
I think I only get annoyed when the artist claims any resemblance is purely coincidentally.