I've always loved the look and feel of Lumiose City, but I just keep getting lost there! I don't think there are many other locations in the Pokémon world where you can get lost so easily, except for maybe the Safari Zones. (Or places that are designed to be like mazes, which I can't seem to recall at the moment.)
15 This brings a question, would ditto transform into Zoroark or into the pokemon that Zoroark transformed into? And Vise Versa?
Is Lumiose like Castelia City? I've never been in Lumiose, but I found Castelia a very interesting city, with a lot to do (but yeah, as you said too, I keep getting lost in there).
Most caves later in the game are pretty maze-y. The Victory Roads and post-game caves like Stark Mountain are great examples of places to get lost in. For an extra challenge, you should try to visit dark caves without using Flash, I've been stuck in the Sinnoh's Wayward Cave for like three hours because of that. (I went in, got to the end, where Mira was waiting, but couldn't find the route back and none of my Pokémon was able to learn Flash.