As far as complexity goes, I think they are tied really, just different approaches to a dungeon design.
I'm just so happy TP is getting some praise now, about time!
EDIT: Also I disagree about the first 3 dungeons in TP being better, in all honesty I think they are about equal. (lakebed tample was outstanding though).
Lakebed doesn't hold a candle to OoT or MM water temple. It was really easy and just involved hitting some switches to fill up the main room. At least it was gorgeous and gave the clawshot some love, though. The final boss was all kinds of wonderful, however.
I for one like Wind Waker's temples more than TP, even though they were unbearably easy, just because they tried new things (and I'm weird, I liked the stealth in Forsaken Fortress) and even let you double-team a dungeon with a second character.