I definitely like the idea, and the art is pretty cool, too. Don't give up on this card; it's a pretty cool concept.
I'm a little nervous about the 'other' cost, though; you could put this in, say, monolight and protect all your sancs with nothing but a couple RoLs in play. The other thing that worries me a bit is the high 6 hp, which puts it out of range of most removal, making it fairly hard to work around. There are a few ways around it, like killing everything else (but then, why couldn't you kill Stolas?) or rewinding it, and there are, of course, still ways to kill it without spending two cards, but there aren't too many.
I think the card probably needs a small nerf. I mentioned having it protect 1 card for every TWO airborne creatures in chat, but furball felt that would ruin it, and that is probably overkill. Another possible nerf could be not to count itself as one of the airborne creatures, i.e. protect 1 card for every other airborne creature you have in play. The idea I like the most, though, is to make the 'other' cost on the upped version more than 4, maybe like 6 or 7. That way, you can still use it in any deck you want, but you gain a clear advantage for using it in an air deck, in addition to the many airborne creatures air has. (though some elements like light and fire have nearly as many)