We are thinking we would put the hand-split cedar shake siding (http://www.gentekinc.com/default/Siding/ShakesScallops/FairhavenSoundSingleSelect.aspx) installed on the front of the house where there is currently the Tudor-style wood trim. On the back, we think the hand-split cedar shake in the peak of the addition, board & batten style in the middle and trimmed separation. We are going to have stone installed on the bottom part of the addition, so the board & batten will do the top half and then the hand-split cedar shake in the peak.
I agree with your use of siding options for the new home. This is a very common configuration of the walls. The board and batten siding will create a classic look on the home that will not look outdated in years to come. The stone on the bottom of the home will create some different textures to the home.