When I was leveling up my [Kuva Bramma], I realized that [Atlas] could avoid the stagger if I kept my feet on the ground, so came up with this for that purpose.

This Umbral Build can punch plenty, but it's not focused on power or efficiency. It's more like a really tanky build that can be almost immune to physical damage. Replaced Tectonics with Elemental Ward. Use 'Cold' Colors to increase your armor even more and resist (bounce) projectiles.

Take a high explosive weapon with you, like a Bramma or a [Kuva Tonkor], try not to jump while fighting, and keep your Elemental Ward and Rumblers going all the time.

You can max out the eximus mod if you forma [Saxum Carapace], but then you'd be preventing your [Atlas] from fitting augments or whatever later if you wanted to do something else with it.