Just my two cents on some of the location ideas posted in this thread:

1) I've always liked the mock-ups (like Bingo's and Angel's) that propose making Geonosis an ash-world. Too much desert in SW anyway.

2) Similar to what others have posted, why does everything in SW have to happen on Tatooine? It has always really bothered me that when they need to hide Luke and keep him safe, they take him to his dad's home planet, to be raised by the only possible family Anakin has left. He knew his wife was pregnant. If he wanted to investigate the possible survival of his child(ren), I'm pretty sure he would start at Tatooine and Naboo. Anakin should be from a different planet (Genosis perhaps, where he goes back in EpII to free the slaves and rescue his mother?), with no reference to the Hutts in the PT. Lars and Beru are two reluctant but compassionate people who get recruited by Obi-Wan to raise this kid because the fate of the galaxy could be at stake. Obi-Wan tells them just enough to convey the gravity of the situation, and Owen agrees though he doesn't really want this responsibility. This explains why Owen doesn't speak very kindly of Obi-Wan or Luke's father.

3) I would like to find a way to give Alderaan more purpose or screen time in the PT, but doing so would almost require changing Naboo into Alderaan. Doing this would contradict the logic I used above (that hiding Leia on her mom's home planet would be a bit too obvious).