I feel like Atlas deals so little damage when the difficulty gets higher than 35. You can barely use it at long distance, since grunts will perform their "desperate" run and go to cover as soon as they hear you shoot, it will probably kill you before the enemy if you use it at close distance, the AoE is only horizontal, only has 3 shots in the magazine. Atlas needs some improvements.
Also make Aneska be able to retreat her mech while moving. This would help a lot.