With regards to Tatooine, I have been thinking along the lines of Owen and Beru being refugees heading there too. However, I think by actually showing this in a way which makes it look like Anakin is choosing to be a soldier in the war instead of staying with his family it would mirror the choice that Luke has in E4. Also we can see how Anakin isnt really family orientated, and then becomes more so as he falls in love with NotPadme and befriends Obi Wan. This could add to the feel of Vader being more solitary after Anakin's fall as he becomes in some ways more like his pre-jedi self.