A multitude of dungeons, a large and true overworld, complex villains in the forms of Zant and Ganondorf, and Midna-arguably the most well developed supporting character in franchise history. You're being sarcastic, right?
The dungeons were pathetically easy, the overworld was barren, Zant was a weakling (although he was pretty cool) and Ganondorf was less fleshed out than ever, and I absolutely HATE Midna (although I hate virtually every support character, I especially hate Midna. I mean, just shut the hell up and let me warp; I don't care if people see me!). So no, I'm not being sarcastic. Emoticon sticking out its tongue.