Dear ;
If we talk about the ” Power Fcator ” of loads, we can improve it only by using a ” Capacitors bank “, but as the inrush current of capacitor is too big, we should be careful if there's in the capacitors bank a big step or big steps.
By the way, the changing of the engine's full system and the alternator's exitation doesn't chang at all the power factor of the loads, because the load's power factor is depending on the specifications of the load itself.