TPM was very much the ugly duckling of the PT and just like the ugly duckling by the end of he film it was the closest to the OT for a small while in parts (like becoming the beautiful swan).

It's hard to know how the cloning plot will be the "missing link" between TPM and ATOC... But it does essentially need a plot device that is relevant or a theme to carry over to the next episode.

I wondered if there were any plans to age obi-wan and give him a cgi beard so this would make all footage from other episodes available but then again that is plots from another episode... He atleast played his part fairly well in ATOC and ROTS but young Obi-wan was not so good... Perhaps that was intentional though as he was still padywan learner.

Some Rob-Roy footage could be used for liam neesom perhaps. But again it's perhaps a stretch

http://www.youtube.com/watch?v=w0-2kzujLA8

I don't know how possible integrating footage from other films in terms of plot and characters or just elements of footage are but using footage from battle beyond the stars or other space fantasy films with model work I would welcome that over cgi.

I think the model work from battle beyond the stars has been used in about 3 films already

As far as gunguns go I don't know if this is possible but they could do with a complete re-design a mixture of Abe-sapien the creature from the black lagoon and swamp thing would be how I would imagine aquatic creatures in a star wars universe not what we got in TPM