I thought for sure the Dark Palace would be one of my favorites, but it's actually not. It's a great dungeon, don't get me wrong, but it didn't manage to rank up there with what ACTUALLY wound up being my favorites.
What are these favorites? Well, as you may have seen from my updated best dungeons list, the Tower of Hera, Desert Palace, and Lorule Castle (in no particular order). It'd take way too long to go into detail as to why for each one, so I'll just leave it there. (Sowwy.)