Back on topic:
Or you could increase the range a bit, and have it deal more damage? Your idea is good too though, this is just an alternative.*Lower the consumption rate of the plasma flamer to 2, or at very least 2.5, similar how the revenant launcher was. Players already need to compromise range (and safety) to use it, so it shouldn't feel entirely inferior so inferior to the bfg and normal plasma fire in terms of ammo consumption. 1 bfg shot easily does more damage than a full clip of plasma blazing, is safer to use for the player, and it only uses 40 ammo, and not 50. and plasma bolts are a little slower to kill, are much more efficient, and higher range.