Re: The Ending Celebrations
In terms of integrating the two trilogies, the closing celebrations on Naboo and Corouscant are crucial. Tatooine and Bespin are nice, too. In general, it depends on whether or not you want this to be the closing act of the story of Luke or the story of Anakin (and Luke). If you're going for OT-only, then cutting them is fine. If you're going for 6-Film-Saga, you gotta include them.
Also, the music John Williams wrote for their 97 addition is actually really nice, and much better than YubYub.