I agree with Xinef. Creature is too fragile with additional drawback of randomly missing the first turn (and with such fragile creatures, first turn hit is sometimes all you will get).
IMO, I'd make it 3|4 with increasing attacks every "turn" of +3 (removing the dive which is usually paid ability that has to be activated).
So...
1) dmg 3
2) dmg 6, heal
3) dmg 9
I know its different in nature to what you planned, but it removes unnecessary random miss and brings more survivability, thus being more valuable in the deck.