And few more thoughts.
If you remove ords, fuel, troops, fighter, bomber and vehicle hangers what will remains in fields? Acks only? That is neither realistic nor "gamey". I believe "factory system" must supplement current system, not replace it.
For example, if you pork ords in one field - no bombs & rockets here; if you pork ordnance factory - no bombs & rockets in all zone fields. Or something like this.