I see what you mean. The ending of EpI almost suggests that the battle is won and everythings fine and dandy -although were there problems with the senate? (or whatever it was called then, to be honest I have problems understanding the politics of the PT, is there a site anywhere which explains it all?!)

Also, you say that ANH had a possibility of just being a one off, I presume this is only because Lucas didn't know whether it would be successful or not as he'd already written all of them and obviously he wouldn't make Vadors ship get away if there wasn't going to be follow ups.

By the way, does anyone know if he wrote all 6 before any of them were films, or just the middle 3. Or is it 9? Or is this something which is argued a lot