The damage from Blow is something you can abuse or combine with first strike or normal creature damage respectively as well giving it slightly better ability to take out big things
You will keep that counter even if Aang, Airbending Master dies
In black, using Bargain should be easy to make Candy Grapple an all-star removal card that can hit nearly any creature in the deck aside from massive finishers in green like Hamlet Glutton
The Mythic Edition of War of the Spark box would grant you all eight Masterpiece cards, planeswalkers from past sets with fancy new artwork
Its worth noting that Malcators Golems contribute to his second ability, so you only need two more artifacts to enter play the turn you play him to trigger his second ability
The flavor is a little off, but the mechanic played well, was generally liked, and clearly ties into Zendikar's land theme