I wanted to see Anakin/The Emperor relationship develop over 3 movies ON screen, and I wanted to see more scenes of The Emperor pushing Anakin towards the darkside, so eventually when it turns it is believable because you can see the influence The Emperor has on Anakin.
I wanted to see the Birth of the Rebellion, and how it started and how they realized what the Empire was doing to the republic, so you can watch Episode IV and realize who fought hard to give Luke/Leia a chance to win in the OT movies.
I wanted to see ObiWan/Anakin on a mission together as good friends for the whole Episode I movie, and just have that cracks jokes and be friends, to show how much they cared for each other, so when they fight in Episode III, you would feel awful it has come to this. Just think of Luke & Han fighting in ROTJ and how you would feel, that is what Anakin/Obiwan fight should have been like.
I finally wanted to see Anakin as cool superstar jedi, and not in the Han Solo cool, but the 'golden boy' cool that many athletes are like. I wanted him to be a premadonna, as he would be someone who you would want to be cause he was sauve and confident, and his arrogance would eventually be his undoing, not his stupidity as portrayed in Episode III.
Lucas wasted too much time in Episode I & II, as they just seem like exposition to the real story in Episode III, and I honestly think if he really started the PT movies with Anakin & ObiWan flying in this huge space battle in Episode I the same way he started with Episode III, and eliminated the crap like Jar Jar Binks, many fans would have really enjoyed the PT, and would probably say the OT is still better, but the PT is still good.