I'd prefer that right-clicking destroys the torch, because there are times early-game where you want to get pick the torch back up because you're working with a limited number of them, and you want to place it somewhere else where you need the light. To that extent, I think it's more useful to quickly get rid of torches than it is to quickly turn them off and on.
That said, a way to quickly click-toggle lamps, lanterns, and other 'sophisticated' light sources would be nice.