Episodes I and II should be ERASED and rewritten. As far as who should do it the answer is simple: George Lucas. BUT he should realise some keys:
-3dCG can't make it all: ESB seems more realistic than AOTC.
-Rick McCallum could take all the "supergreat" characters like jar jar and similar and go to the bottom of the sea where he'd be happy without oxygen.
-Less action but better, less characters but stronger dialogs.
-and the list goes on just to make the new trilogy match in anything appart from the names to the old one.
Matrix won the Oscar to fx(altough they were worse than EPI) because they seemed more realistic.