@jwatte I like your suggestion about disabling gravity and working in velocity space and not force space.
In practice, are you suggesting using SetPhysicsLinearVelocity to model the effects of gravity, lift, thrust, etc? In the docs it says this about SetPhysicsLinearVelocity:
This should be used cautiously - it may be better to use AddForce or AddImpulse.
This gives me hesitation, and matches my intuition that directly setting velocity will interfere with the physics simulation.
Or, is there some other approach you had in mind?