One way of easily making the unit less more retardedly strong is removing one of it's guns.
Why does this particular unit gets TWO flamers while everyone else have one?
and to all the retards saying "j-j-just stay away!11!" well, you can't, because for some reason the flames "supress" all infantry (they hit the dirt or run around looking for cover) every time they get hit by flames making them unresponsive, just like the old guards dance bug.
Reduce the DPS, slightly, problem solved.
Also I think the damage it does on garrisoned units is actually a bug.