What needs to happen to get Unity 5 to implement a extensible system that gives the user the ability to add more inputs to lights? If created correctly we would need the availability to support both forward and deferred rendering mode and possibly keyword support associated with these inputs. The biggest justification for this feature is that it would allow us to support many different kinds of area lights. We could make Tube, Disc, and Rectangle lights because the engine could support them were it not for the lack of inputs in the UI
Provided game developer control over individual controls associated with lights. For instance I want the ability to control if a light source will show up in a glossy floor or not, a toggle would be more than enough to satisfy this. See images attached called light source in reflection to illustrate when it would be useful to be able to turn source light reflection off.
Finally additional Light Debug Mode:
I want a way to determine the cost of my dynamic lights in a scene. Having a debug window that only displays how lights are effecting the environment and the cost of the lights is a must. Artist need quick and accurate feedback when lighting there scenes and I believe this kind of implementation would help. I hate to toss this example out but the lighting complexity image attached is an section of the documentation of Unreal to help illustrate what we are viewing.