this is something im thinking about ever since the first time i play CDDA…
fire mechanism in CDDA is somewhat unrealistic because walls can catch on fire easily even if its made from material that is actually hard to burn in real life, plus corpse burning is too easy, just activate lighter and set corpse on fire. while in real-life to burn a corpse easily like that you need gasoline-doused corpse and a lighter to do that (or this could be referencing The Evil Within game mechanism where undead corpse needs to be burned with lighter to truly kill them)
but still, i love the fire capability to spread and be used as alternative crafting food, since Far Cry series i love to see fire spreading mechanism as it gives the player possible strategy and even escape plan in case of bad scenario + realistical fire hazard.
i think there should be flag for tiles like NON_BURN or HARD_BURN so that tiles with this flag will be hard to burn or not burned at all by the fires.