Would be cool to use Soul fire torches to lit space under water.
Professional divers use such things in real life.
Since it "magic" fire, it is possible from the logical point of view.
Also, crafting recepie for Soul fire should not use coal. There is no coal ore in Nether. You should be able to craft this torch using only ingredient available in Nether. (Same for Soul Campfire)
Maybe bonemeal instead?
Coal is obtainable in the Nether through killing Wither Skeletons. The recipe is fine.
Watch out for the crabocalypse. Some say the day will never come. But it will.
Feel free to drop by for a chat whenever.
If you'd like to talk with me about other games, here are a few I play.
Team Fortress 2
Borderlands series (Borderlands 2 is my favorite game, ever. TPS combat is a lot of fun and makes up for the lower-quality story, in my opinion)
Elder Scrolls series
Warframe (IGN is something like That_One_Flesh_Atronach)
Pokémon series (HGSS forever)
Left 4 Dead 2 (Boomer files always corrupt though)
SUPERHOT (SUPERHOT is the most innovative shooter I've played in years!)
Dead Rising series (Dead Rising 2 is one of my favorite games, and the 3rd was a lot of fun. 1st has poor survivor AI and the 4th is bad)
Just Cause series
Come to think of it, I mainly play fighting-based games.