That's a pretty solid standard Battle Sisters list. My suggestion though would be to drop the braziers and trade your regular flamers for meltaguns. Heavy flamer/flamer/brazier might devastate horde troops, and it will even cut up MEQs with divine guidance. But vehicles will laugh at you. Armies with lots of transports and/or dreadnoughts will give you such a headache. Winning tournaments is about having a good chance against everyone equally since you never know who you'll fight. If you go all anti-horde, you will struggle against mechanized enemies. People generally tell me "hey, two exorcists is more than enough." It is, if luck is with you. But Exorcists might roll 6 shots and blow up a tank every single round, or they might roll two shots and miss every single round. Or, the enemy might blow them up on turn one. Especially with how much more resilient vehicles are in 5th ed, you need to hedge your bets with hedged bets so you're not just likely to take them down, you're sure.
I've been saying this for a few years now, but people still don't believe me-- Battle Sisters win by using mobility to combine overwhelming forces against single targets. That's why heavy flamer/melta works. You probably can't wipe out a powerful unit with one squad, but you can with three. Even if you have 2-3 flamer templates in each squad, you still need to combine squads. All it takes is the powerfist vet sarge surviving to tear the crap out of one of your units, and if you rely on luck to wipe out the enemy to the last man, that's what will happen to you. Like I always say, if something is worth destroying, it's worth using overwhelming force to be guaranteed of destroying it. If something is not worth using overwhelming force on, a Battle Sisters army probably should use mobility to avoid it or Seraphim to tie it up for a turn. And when you follow this doctrine, the benefits of versatile squads are realized, because no matter what you need to kill you have the overwhelming force available to turn it into a smoking crater.
