The lifegain is useful for a deck that wants the game to go long
Boltbender Ecstatic Electromancer Embermage Goblin Fissure Wizard Goblin Cruciverbalist Goblin Electromancer Goblin Flectomancer Goblin Pyromancer Goblin Researcher Goblin Test Pilot Goblin Wizard Izzet Chemister Krark, the Thumbless Mizzix of the Izmagnus Mizzix, Replica Rider Skoa, Embermage
A drop that includes three board wipes in Day of Judgment, Star of Extinction, and Toxic Deluge would already be frightening, but adding in an extra turn spell in Temporal Extortion, and a way to exile key cards from your opponents' decks with Praetor's Grasp makes this by far the meanest Secret Lair drop we've ever seen
She can be a flyer-matters or an enchantment/artifact-matters leader, or you could combine them and run flyers that are artifacts like Steel Hellkite or Baleful Strix
When did you begin playing Commander