You do have some points here. I just did some tests and it seems the glowing spot glitch disappears if you go into the light settings and turn off multiple importance sampling (though I have no idea what the impact of that would be in a complex scene).
I think I have found some better settings:
glass: remove visibility for diffuse and shadow
emissive mesh: remove visibility for diffuse and shadow
light object: remove visibility for camera, glossy and transmission
Also, you can get less noise by deactivating reflective caustics in the render settings, as the emissive and glass will still create them together.
Here is my test blend file. Everything works in that small scene, but I would have to test it in some more complex scenarios.
light_bulb_test.blend (961.2 KB)
