See, the problem is that the things you're saying could come true. I mean look what he has done so far to the trilogy. Why stop? The best example is the added scream of Luke in TESB Special Edition. Then again he took it out. What about the "original vision"???

Well coming back to topic: A CGI Yoda would not help the movie. Although I do think that he is way better than the puppet in Episode I. But I don't see what could be added to a possible Episode I Special Edition. It's becoming more and more ridiculous...