I have never read the novel, was Anakins turn longer and different, I know the book was much more intense than the movie
It would have been a good idea for a 3 hr Star Wars, (but would Lucas want it too run that long) as this was the most important film in the prequel maybe saga as it covered Anakins descent and turn in to evil (which was considered weak by some- people) and the other important points such as The Rebellion scenes etc
It would have been interesting to see it as an "R" (i assume your highest rating) with the scenes but would the key SW audience be unable to attend(I am not to sure on the American Rating System) and it would definatly play on Lucas/Lucasfim mind, I know they had problems with the U.K censors over AOTC they had problems with a headbutt(Jango and Obi Wan) and were offered it uncut at a higher rating, but took the slightly lower rating with the headbutt cut out