thanks for the advices!
Something fun to do with Heavy Flamers is go specialist Poison 4+. It essentially lets you reroll the wounds with it because how often do you encounter better than T5 in Kill Team? It's not very common. I think the only guys who can do it are Chaos Bikers/Nurgle Spawn, which granted are really great in kill team.
That's a very good idea. I know that someone will bring Nurgle bikers but hey, Melta are here for this.
I am going in with this list:
5 Battle sisters : Sister superior veteran with combi flamer (leader), 2 battle sisters, 1 sister with flamer, 1 sister with heavy flamer (specialist: poison)
5 dominions: Sister superior, 4 sisters with melta (one specialist: Master craft, one specialist: infiltrate)
Taking the veteran for the increased leadership for break test.
I will see how it goes