This chart shows the various options and consequences of the different possible Brexits (click on to see a bigger version). I think the ones worth pursuing, which are both politically feasible, are the two options on the left hand side. Unfortunately one gives too much power to the European Court of Justice and the other makes free trade in services difficult. So some tricky choices looming.
I still can’t see a finalised deal being in place within the two year time limit so some form of ‘kicking the can down the road’ is, I think, the most likely outcome. I agree with Wolfgang Munchau in the FT that the UK needs to have a worked up Plan B so we can realistically threaten to walk away from the negotiations at anytime.