Flame tounge weapon is ok, but majority of the time its Wind fury or Rockbiter being used.
there exists a rare effect on a polearm that i feel would be very neat to add the effect to Flametogue weapon. keep the numbers small but have the effects be the same. that polearm is Flame Wrath from BRD.
chance on hit: to envelop the caster in fire shield that increases fire resist by 10 and returns 10 fire damage to attackers for 15sec, and does a flame nova for 130-170 damage.
If we took this and just added the to existing FTW effect of flat fire damage on hit, we can make a neat tool for tanking or dps alternate weapon imbue.
This effect of fire damage return to attacker i beleive scales with SP so shamans who use some spellpower items can gain a lil help while tanking in addition to items like nagelring and skullflameshield.
So if we did this i would scale it down rather low so the AOE effect was far more docile to balance the fact you get so much effects on one proc.