Very atmospheric yet a bit unsettling to play always made me expect I'd see something slide away when I threw an ember into the darkness. I really like what you're going for here it has the potential to be a real gem of a game I look forward to seeing how it grows.
It does feel a bit frustrating to find the light sources as it is, they are hard to spot even when throwing embers, but increasing light ranges would definitely ruin the atmosphere. Maybe the terrain can help a little bit more in guiding you towards them.
I suggest adding a hint for ember stacking I'm sure many players will miss that you can just buy a bunch for longer effective light duration.
Good luck with your project!