I totally agree with you Tom. I was very disappointed when I heard Williams wouldn't score JPIII, and I was even more disappointed when I read the reviews on the discussion board. But when I saw the movie I thougt the music was quite ok, and when I bought the CD I was very surprised! Davis wrote a fascinating action score, the complexity of which is to par with a Williams. The integration of the old themes is well done, and the overall result is exiting fun and refreshing!
About The Mummy Returns I wanted to say that I, unlike you, did expect a good score. Alan Sivestri is one of the most underrated composers in Hollywood (Hans Zimmer one of the most overrated ), his talent is even more flexible than that of David Arnold, and his use of orchestra and choir is just amazing. I think Silvestri would have done an even better job than Davis did for JPIII. Maybe an idea for JPIV ?
By the way, The Mummy III (The Scorpion King) by John Debney will be great too, I bet.