The biggest thing for me was just the large learning curve of the game. Took me forever to figure out that combat was a lot more concerned about timing than Twilight Princess. Also, the celestial brush took a while to get used to, but after a while... everything just clicked.
Also, I loved running around as Amaterasu in the game. You know a game is great when just running around is fun in itself.
And yes, the Blockheads were just awful. I actually had to record the last one because I just could not get it. And I wanted that bead!