Morgan's strategy in the ODI side is a good one to look at - if Stokes and Moeen are both available then the side is 5 batsmen, keeper, 2 allrounders, 4 bowlers. If Stokes isn't playing, the balance of the team changes as we don't have a direct replacement. You can replace him with a bowler, or a batsman, or forget replacing him and rethink how you balance the team. Replacing with a batsman leaves an attack of 4 bowlers plus Moeen - no good as Moeen is a luxury bowler rather than dependable. Replacing with a bowler leaves us a batsman light, so what do they do? Change tack and play 6 batsmen, keeper and 5 specialist bowlers = no space for Moeen.
Given Stokes isn't coming back any time soon, let's hope they have a proper think and rework the team properly rather than just picking an extra bowler and bunging everyone up a spot. Personally I'd consider a top 5 batsmen, YJB/Samit whichever way round, then 3 seamers and a specialist spinner. Maybe Crane takes loads of poles at Sydney and a star is born, maybe give Leach a go, who knows.