I try to have a pretty balanced offense, so you may tweak this for your air-raid, but this is how I set up my playbook.
You typically are allowed around 360 plays and a max of 40 formations. I run a balanced spread out of the Pistol and Shotgun and try to use around 24 or 25 formations which allows around 15 plays each. In each formation I typically have 6 run/option plays (an outside run, an inside run, a counter, read option, triple option and speed Option) and 9 pass plays (a playaction rollout, a couple screens, and around 6 pass plays which usually includes Stick, Strong Flood, Mesh or Shallow Crosses, and Verticals).
6 run/option plays x 24 formations = 144 run/option plays
9 pass plays x 24 formations = 216 pass plays
I think this setup allows me to have enough variety of different formations and play types in each formation.
Hope this helps.