Yeah Petal is great here. I just doubt that OUAT is the correct cut. As bad as they are past turn 1, you also need 4 copies to maximize seeing it on turn 1 and this deck is all about the turn 1s. Hanni's build had 4 OUAT + 4 Petal.

I would cut 2 lands + 2 other slots to make room for 4 Petal. 16 lands seems like too many. Petal also makes it easier to make T1 Kitchen Imps and play through Daze.