exactly. I would do a doubletake on someone saying the, for example, Eiffel Tower was "awful", in the origional sense of the word. and yet, even awesome (as explained above by BigJ), which uses the full "awe" and not "aw" which is most definately defined as archaic, is used to describe the best possible outcome or experience or feeling.
I like the idea the word came from a butchered form of ege, but I can;t rule out the possibility of a historical slang background. We use slagn everyday and even manipulate words to express something totally different. Like "wicked" as something "cool" which in turn means something pleasurable or "neat" which in turn doesn't mean pleasurable, but organized. lol. kinda fun tracking down slang. So perhaps sometime in the past, someone used awful as something bad (like wicked for something good nowadays... actually, that slang term is old, but you get my "drift". LOL~!)