Come to think of it, Battle of the Heroes was really well done for ROTS too... I actually really enjoy the Episode I soundtrack and give it a listen every once in a while when I listen to the OT soundtracks. I thought it was weird that they recycled music from TPM for the other two prequels (examples being podrace music during the scene where Gunships invade the arena and Qui Gon funeral music being reused for Padme's funeral). I wonder if Williams was simply unmotivated because Ben Burtt was drowning his stuff out with goofy sound effects.
I bet the prequels were a bitch to score with all of the editing and jumpcutting from locale to locale. The songs themselves are great on a CD (Duel of the Fates, Battle of the Heroes, etc.) but in the context of the films they got a bit muddled and lost some of their impact.
Speaking of editing, I hope for VII they do away with a lot of the screen wiping effects when going from scene to scene. They're fine when used sparingly but they got a bit overwrought as the prequel progressed.