The word 'supernatural' isn't terribly useful, actually. This came up in a recent Atheist Experience episode. Lightning, for instance, was 'supernatural' until we figured it out. Then it became ... natural.
Now, I agree that agnosticism is the most logical position, that's why I'm an agnostic atheist.
Do agnostic theism and atheism indeed require similar leaps of faith? Well, let's look at the track record of the two. In every single thing we've ever figured out, the answer turned out to be ... not god. Regardless of which god you care to insert there, the answer has time and again been ... not that god.
So, we have this thing we want explained, the start of the universe, and, yeah, there could be an intelligence behind it (like I said in my previous post). However, theists by definition, try to drag additionals attributes into the discussion, while the utmost you can reach logically is X can create a universe. Yet, theists like to add on, and X can do anything, X knows everything, X loves you, X listens to you, X rewards you after you die, X can also punish you after you die, X once knocked up a virgin girl, ... the list goes on.
Is that still ... remotely ... logical?