Roiling Dragonstorm ( ETB, R ) - Regularly allows you to draw two cards and discard for 2 mana
In a vacuum, specifically a vacuum known as Kaladesh, Aetherborn looks fine, plays fine, and feels fine
Use your early-game Eldrazi creatures to generate mana for your top-end haymakers
Despite having a low budget, Siona is one of my most powerful paper decks: not only is the deck an Aura Enchantress deck, which has an incredibly deep pool of strong cards to work with on a low budget, but it's also able to quickly and consistently combo off thanks to the interaction between Siona, Captain of the Pyleas + Shielded by Faith to generate infinite Soldier tokens and the backup combo of Siona + Reins of the Vinesteed + a sac outlet like Blasting Station which similarly generates infinite tokens to sacrifice and win with
Commanders Plate Commander's Plate is probably the single best equipment for the Commander format
Also no (that title probably goes to Ghave, Guru of Spores)