Coal turning white as it heats up to fire temperature isn't difficult to do. We have the heat colors used for WIFI and for heat gradient that can do this.
A good base of my Idea, just without the rapid combustion of the Coal. This is mean't to dressup the coal rather then change it's current properties. But good job.
Some further insight into my idea would be this.
Under normal circumstances coal burning in the general atmosphere of powder toy would have the dull glow like I was saying in my original post.
But lets say if you make a blast furnace, where you would be forcing more Oxygen or even Liquid Oxygen in to the coal it would glow brighter due to the higher temperatures.
This combined with the effects of Fire, Lava, and the other options in TpT would allow for some pretty Coal Smelting Plants, or even a Metal Forge.