If we want to have different types of conventional fixtures in our rig display, we have to create a new type. IE I make a copy of dimmer, name it Fresnel, and set the Fresnel physical model for that new fixture.
It would be convenient if we could set a default Beam / edge for that fixture. That way I could model a S4 50Degree, S4 36 degree, etc It would save a small bit of work for me.