>> did you ever want to keep it burning?
It might I'm speculating here, but I see your question as a question from a game developer who want's to create a mechanics which would hold a player in the game.
In my opinion, there is not enough that "tamagotchi" effect yet, as the "investment" is quite small - just continue clicking.
I definitely can see an interesting survival game with such simple mechanics though, especially with this philosophical/existential theme about dark vs light.