#controller of an ability

[magicjudge]

If I enchant Humble Defector with Freed From the Real and activate and untap it a few times, and then allow those all to resolve, will it always be me drawing the cards, or will control of Humble Defector at the time of resolution mean the target opponent draws most of the cards?

You control Humble Defector's ability because you're the player who activated it, therefore you're the one who draws the cards. If they wanted the current controller to draw cards, they could have worded it that way, but they didn't.

So you can draw a lot of cards this way, sure. Your opponents likely won't want to give Humble Defector back to you, though.