From the item descriptions regarding Arstor, it does seem like he is an engineering oriented scientist more than a magician, so this kind of seals the deal. Not saying that there couldn't be a mad scientist in Astora, but we already KNOW there basically is one in Carim.
The fact that knight & elite knight armors have blue in them doesn't really mean anything. Besides, some of the areas in the trailer have nothing to do with the game. They said there will not be snowy areas for example, even though the trailer has some.
And trust me, there is more information about Carim than Astora in Dark Souls. Go and talk to every NPC and read all item descriptions again and you'll see.
The crow flying higher when it leaves from the Asylum doesn't mean anything... You're over-analyzing things quite a lot to be honest. Or are you a bird expert?
The dragon could be the Evil Eye. This is your only reasonable argument, the rest was a bit far-fetched.