(Note: A lot of my previous suggestions sucked, and that's because I didn't know what I was doing. I'll use some of my improved suggesting skills to hopefully make up for that)
Lighting up snowy areas can be a pain, with any light you use melting it. It's really inconvenient, and it would be nice if there was a way to actually light those places up without harming the environment. So, I introduce to you, the Magic Ice Crystal!
(Note: Crafting yields 2 Magic Ice Crystals)
Magic Ice Crystals are new light source blocks that will not melt any snow layers they light up. Their appearance resembles a blue crystal with a glowing "core" and can be placed in any orientation, but will break if the block supporting it is removed. Alongside crafting, they would also generate in Ice Spikes Biome, giving an alternate method of obtaining them. This would be useful for lighting up places that are usually hard to light and for another unique block that could be used in a variety of builds.
Thanks for reading my suggestion! Let me know what you think in the comments!