I can't say he never had an original vision, because, obviously, the first plan he had was technically his "original vision". Whatever it was got lost in the translation due to success, greed, and no one there (like Gary Kurtz) to keep him from doing whatever whimsical thing he wanted to. And, yeah, most of the stuff you wrote are direct results of him just making up prequels as he went along and trying that whole fan service routine (like the droids, Chewbacca, and Baby Fett). I still don't see why people have problems with the whole "He wanted you to have this," line. It seems pretty clear that that's just another one of the things Ben told Luke to make him think his father was a great person. As Darth Simon and countless others have said, it's better than telling Luke, "I took this from your father after I chopped him in half and left him to die."