The steer force in boids or LJpotential is a vector, the angle is "Expression:ForceAngle", and the scale is "Expression:ForceMagnitude" in polar axis. Or ( "Expression:ForceDx" , "Expression:ForceDy" ) in orthogonal axis.
But I only use "Expression:ForceAngle" in my sample. I would try to make another sample which using both boids or LJpotential behaviors.
Car behavior is one of possible moving behavior, it might use physics behavior, or just move sprite with bullet + set angle.
Sorry I had missed the last section. I prefer to make 3rd plugins even in C3.
The philosophy of official plugins might not be the same as 3rd plugins. Official plugins should be stable to become the foundation of engine/event sheet. 3rd plugins could be more aggressive.
I am interested in mapping requirements into well design plugins + events.