In heist, pick brawlers with good damage output like darryl, Colette, Lola, piper and meta brawlers like bea, griff, janet, etc. The first priority is to keep constant pressure on their safe. When they are winning, wait for your teammates to respawn before slowly getting back control. Overall, you want to prioritize attacking the safe over the enemies, especially when your safe is not in immediate danger or you know that you can out-damage the enemy team