Field of fire no, incinerate does like 9 points of damage a hit so making it aoe isn't going to make it any better.
Blazing fire is only really useful for applying incinerate x5 quickly to a group of mobs so you can detonate them quickly.
Blessing of amher is great in group pvp where you are just at the back nuking.
Black ashes, again to do with detonation
Agonizing fiery torment is fantastic since you can instantly cast it when its feated.
Adding all 5 features in blessing on amhra, is there a good change in damage? Reason I asked was it was difficult to see a difference when I put all 5 pts on it. Maybe I am wronge, maybe something I did not notice, will like to know more from your experiece.
Black ash, main purpose is only to detonate a large amount of players after BoA was released?