Yeah i was quite let down by the lack of importalisation too. I like your ideas.Basically the previous save file doesn't make any actual difference to the game apart from your mum or dad being the previous king or queen. When they said the previous game will transfer on to your new game, I thought it'd be like mass effect where the import actually effects the new game.
Maybe something they should've thought about was at the end of Fable 2 was the final descision (which was pretty epic):
If you took the money for yourself - You were given some extra money to start in fable 3
If you saved your dog and rose - she should make a small appearence as an old woman or something in f3.
If you saved the population - They should give you lots of gifts etc or should be more easily influenced by your friendship.