If I were to improve it I would probably remove the blue and purple in the flame/only use one of them, make the guys in the foreground less robotic looking, and make the guy in the fire look more like they have been in a fire, and less like they just appeared there.
Oh i see. Like the fire is going-on for X amount of time already.
An advice would be "simply make smoke around then?" but then it wouldnt fit your idea of "on fire" (and not extinguished)
Also dead body ? Or struggling man on fire?
(btw one easy solvable flaw, is to reduce the size of the fire)
Still alive, but barely, a smaller fire could also work. I was thinking more making the person look more burnt. Forgot about smoke, don’t know how that would mesh with the color scheme and lighting…