Would be nice to have a setting the turns off shadows for emissive materials that have visible to eye turned off. For most studio lighting for cars you'll be using object lights without shadows, only for reflections; IE, kickers and duve walls. A simple check box option would be perfect, as there might be cases where you'll need both.
Agree - we are looking into this one.
In addition, it would be nice to have every material with options for "visible to eye or visible to reflections." Then you could make parts invisible but still reflective which would be handy for glossy ground passes, ground indirection illumination passes, ground caustic passes; basically anything with a ground or set extension.