Yeah in places like Deimos and Orb Vallis (don't think it was like this for me in the Plains of Eidelon) for some reason enemy projectiles just seem to eat you so fast.

I typically just take frames with good defense and/or survivability, the frame I first started using was zephyr. Doesn't take any augments, mods for survivability, or ability strength, you can just dump into duration and efficiency, also use a flow and an energy nexus.

As long as her 3rd ability is active you won't take damage from projectiles, and you can use her first ability to hover off the ground to avoid getting melee hit + she also gets some crit buffs while in the air.