I feel like the turning tail slap, while it is a good idea, would be a lot harder to animate, and make the attack last at least 3 or 4 times as long. I don't mind the tail from the ground so much if it's quick, easier to animate and makes the game come out faster.
As for the appearance, i feel like a Sea dragon would look a lot more tame than say, The PyroHydra (Blaze, Abyss, and Czars). Namely because I kind of picture it to be smaller/more nimble as it would move through water and need to be aerodynamic, As comparison to the PyroHydra (Blaze, Abyss, and Czars) which was a large/fat land dragon in a rocky/aggressive land.
I kind of like how they were different honestly, instead of having all super aggro looking spikey dragons, he mixed it up. :S But to each their own, right?