In those instances where you want to see the light source in a reflection, I turn off the light's reflection visibility and use an actual model of the recessed light with a light material on the filament. That way your scene direct/indirect light is coming from the light object, and the reflections are reflecting the geometry of the downlight housing and filament.
The only thing you'll have to manually tweak is the intensity of the filament to look right in the reflections. It's a good way to control the glare coming off of reflected light sources too.