cgi Yoda is a lot closer to Freeborn's vision than that mean-looking terrible puppet in Phantom Menace which looked more like a Gremlin, re-doing his scenes in TPM will be one of the few changes George has made that actually improve the consistency between the 2 trilogies, as for the possibility of replacing the OT puppet, I really can't think of a shot in the OT that would warrant being re-done, 25 years later it is still astounding the life they managed to create from the original latex puppet.