For a deck that is reliant on its commander, theres precious little protection for him, but a lot of good artifacts, enchantments, and big, high powered beaters like Etali, and Ghalta, Primal Hunger to beat down on your opponents
Past her applications against Burn, Shalai shuts down targeted discard as well as edict effects from cards like Liliana of the Veil
Cards like Waterbender's Restoration, Extravagant Replication and Thassa, Deep-Dwelling repeatedly flickering your Aether Channeler and Riftwing Cloudskate gives you an incredible advantage because your opponents have to recast the same creature over and over (this is trickier in our era of powerful enters abilities, but still works)
Cascade, Cascade, Cascade (It Stacks) Cascade is a powerful design space to work in, for multiple reasons