Prospero thinks he's the puppet master. Well I say nuh uh.

Prospero is the typical manipulator, thinks he has everybody wrapped around his finger.
First of all, he has a slave, who is gender- and visibility-neutral apparently, that conducts all major tasks for him; in other words, anything Prospero wants accomplished, Ariel does for him. Ariel "[carried] out [a] storm just as [he] (Prospero) ordered." Personally, I don't see why Prospero couldn't have done this himself, when he seems to have nothing better to do than to tell his daughter his dukedom sob stories that evidently took place when she was too young to remember them clearly. There are more appropriate times and places for story time, dude, if you thing you are SO important; just saying. Anyhow, Ariel asks that he gain his freedom back, and Prospero replies, reminding of the "torture [he] freed [Ariel] from." All the dude/dudette wants is his/her freedom back. Not so much to ask. Prospero then bribes this Ariel character with a supposed release in two days. Well, why not right then and there, hm? I have not read ahead, but judging Prospero's puppet-master-like ways thus far, he will keep this bribe going; "Do this, Ariel, and you will be free in less than a week, I promise ye," and so on.

Also, Prospero likes to repeatedly make certain that his "listeners" are "listening" at all times. He kept nagging Miranda about listening/paying attention when he was telling her the story of his brother. "Please listen to me carefully....Do you hear what I'm saying?....Now listen....Just listen a little more....Sit still and listen...." Well shoot! If she wasn't listening, you would know, especially since she is your own daughter! It seems to me that firstly, Prospero is painfully insecure, possibly because of how he was shoved from his dukedom but his own flesh and blood. Secondly, realizing this, I think that his atrocious insecurity is where his manipulative habits take root; he wants to ensure that all are on his side, since they seem to not have been in the past.

I may be slightly to completely off in my judgments, but as of now, this is what I have observed and do believe.