The margin should be fine, provided he keeps it clean and error free. Dumoulin - just the world TT champ - will be eyeballs out and ready to pounce on the slightest slip or sign of weakness.
G would be a very worthy winner, but let's not forget that both Froome and Dumoulin rode the Giro too. There's a reason why GC riders generally don't! Because of that I'd say Froome is still just about Sky's alpha male, and we saw that in the riding order until recent days.
Bernal has been crazy good in support up in the hills. Think he'll have earned himself a massive pay rise. Sky will want to keep hold of him.
The Yates boys have done their apprenticeships elsewhere. About time they were bought in to the Sky fold so they can actually start winning things.