Right but my guess is this will come later because it probably need quite some code. OR they may go the realistic way with no light at all but then the miners would need some individual light (perhaps with a special helmet?) or the player would have to manage light with torches or something… (but in any case, much more code is needed!)
There’s this similar (but not the same) bug from long time ago:
But I’m not sure about it, since each computer has its own configuration for the shadows, there are computers than can’t apply the AO and others that have good graphics.
Maybe this could be moved to suggestions. I’m not sure if the light is meant to be shown in situations like in your image or not.
Or, we could page @not_owen_wilson to ask him whether the improvements you suggest are planned ( / will be revisited) for the long term or if the current implementation is here to stay. 