Lets get started here:
430.24 says that in this case you need to have a conductor ampacity determined by:
(1.25 * Largest motor) + (Sum of FLC of other motors) + (1 * noncontinuous non-motor-load) + (1.25 * continuous non-motor-load).
I checked the exceptions and didn't see a note for your situation. I'm guessing you don't need a code cite to size your wire
On to the Overcurrent protection:
430 Part III gives your motor overload requirements. 432(C) says to size the overload based on the motor service factor. SF >= 1.15 or temperature rise 40C or greater is at 140% and all other motors at 130% max. I'm assuming you are using starters/overloads on them. Each motor needs its own overload. Sorry, but I don't have a cite on this one and not sure where it is at.
Ground fault and short circuit detection:
430.53(C) has the information regarding your specific situation. There is a bunch in there, but you use table 430.52. In particular, you want 430.53(C)(4) where it says to use the following:
(table 430.52 value of highest rated motor) + (FLC of all other motors) + (all other loads on circuit)
If the above is less than the calculated ampacity of conductor sizing, you use the ampacity of the conductor size.
I took the more liberal route here because you are starting two motors at the same time always.