Survival alternative to Light Block: Souls Lights

The inspiration behind these souls lights would be the atmospheric ghost lights (called onibi) we often see in Japanese media and folklore. This purplish/blueish flame block could be placed floating anywhere and is only visible when holding it in your hand.
Its crafting recipe could be a bottle of dragon's breath surrounded by blaze powder, and it would produce three souls lights. Once placed, it gives a light level of one, but you can change it by feeding it with coal or blaze powder.
Coal would increase the light level by one, and blaze powder would increase it by five. Also, as the block would only be interactable when holding it in your hand, you would need to have another one in your left hand when feeding it. It would make you look like a wizard!
Finally, it would probably have a gorgeous animated texture, so it would be cool if it can turn visible. Maybe by giving it a ghast tear. As you can see, all the item choices make it a very end-game light source. And it would also give dragon's breath another purpose.