Most complex tank class?

[Tr4c3r]

I am currently playing a dwarf warrior and have got him to 20 so far. I am just wondering what to most complex/hard to learn tank class is. I really like tanking its just that for the warrior for the past 20 levels all I do is spam taunt and kick. From what i hear this doesn't change much either. Any opinions are fine. Basically just tell me what you think is the most complex tank class and WHY.