Yes there's no getting away from it - a lot of spawn files need to be written to get interesting results. Fouteman used to put a lot of picktype entries into his aircraft xdps, and said that, despite the limited list of picktypes in the SDK, his unique picktypes worked on testing. It allows for better differentiated spawning.
I have a much better handle on attaching spawn table files to facilities these days, and so can use facilities geographically located in the global_layer, to trigger air spawns belonging to specific fighter Groups, for example.