Have a mode which you can manually set how turned on your guys and girls are and a manual orgasm button.
Either as part of or following selecting a position allow manual choice of location rather than having to continue selecting the same position untill it chooses the place you want.(This could be done by hot spots appearing when you press a key and clicking on one moves the action to that location).
Random variation changer can be activated for a position with variations and over time(user defined?) it will automatically shift through randomly the variations for that position(including the default).