With another decently big +1/+1 counter creature just added (Dragonborn), I wanted some other minor payoff for the counters: Duckshell Crawler seems perfect. And having cut Faerie Vandal, blue feels like it doesn't add much to the archetype besides Amass - which black has more of - so I'm trying out the Skymage. It's possible it should be Thopter Mechanic, or swap back Mystic for Vandal (Mystic played well last draft), but Skymage seems like a decent engine piece and high-risk-high-reward play.
Academy Elite has felt narrow, wordy, kinda weak, and also misleading for anyone looking for +1/+1 counters.