Here I would like to propose some changes for coal.
Changes
The randomness. Currently Coal begins burning at a 1 in 500 chance. Every frame fire touches COAL 3 or 4 contacts are made. The randomness should be removed to some extent and replaced with a new way:
The way Coal lights should be based on burning materials around it.
Coal's chance of lighting from randomly drawn fire should be doubled.
Coal adjacent to burning coal should light easier.
Coal turning into Broken Coal under pressure should be moved to powder.h //there are other conditions
Coal's burning should have a few tweaks
02 would increase the chance of coal burning
Coal needs PROP_HOTGLOW
Uses
Adaptable power source for powerplants.
More complex thought out, fueled creations.
A subject for a competition.
Different levels of 'burnage' can be created
Burning stick-man has never been like this before!