There are about 3 cafes around the car park just off the ferry, all of which do a good cafe et croissant. Nothing too special. Try the Broch d'Argent, or the one next door. We never found anywhere worth stopping at on route, unless you get really lost.
Paying six quid for the waiter service breakfast on the boat was popular, because it properly cooked, (butl a bit French) and its all the croissants you can eat, plus free coffee and juice - fill your boots!