I'm sorry ken, but I have to disagree with the way you have yours wired. The mag-starter should open both legs of the 220. You have one leg opened three times and the other leg is always hot. The two line wires should connect on top and the two load(motor) wires on bottom. The third leg or side is not used at all and only two Melting Alloy Relay Blocks are used.
The pressure switch on the tank controls the starter. You need one other item. A manual fusible disconnect switch to feed the mag-starter. Wired the same as the starter. Two in, two out, and one fuse on each leg.
10/3+grnd?? Are you thinking of using UF or NM plastic sheathed? If you're pulling a permit, the inspecter will be happier with two Black THW or THWN + a green inside some conduit.
