Perhaps I'm late piping in but...
Put me down for the Plate over the Connecting Girts - Make the Common Purlins continuous - And I'll put in a vote for the sills. All part of the cohesion and redundancy that are particularly important if your foundation is less than completely stable and might maybe heave a little. To have a building move as a unit is better than it if moves in subsections.
6" Granite curb (sold way wider than you'd guess) set into a rubble filled trench, with proper perimeter drainage makes for a stable and beautiful foundation for outbuildings but at $15 a running ft just for the curb, it's not cheap and more than you need for a woodshed.
There is a boneyard of broken dreams available for the picking up behind the Concord granite-works up at the quarry that might yield some big chunks to bed your shed on. It's a great source for both big rubble and little chips for shimming dry laid stone.
If you are yet to order your timber, remember that small scantlings (those less than 5X5) should be ordered FOHC - Not every area circle mill can or will do this, and it may well cost a bit more, but you don't want to frame anything with little sticks full of pith. It's unstable and checks heavily. Go in knowing what you want and why and you'll be treated fairly.
The tornado crossed my town also, (my road for that matter) and I may be in the neighborhood, I could maybe recommend sawmills or whatnot.
