The 7/7 body is massive and can be cast simply by paying and tapping another four fliers (plus commander tax, if any)
Cutting these in favor of more Aura support creatures like Light-Paws, Emperors Voice, and thematic card draw like Enduring Innocence, is a good move
By playing locations with John Silver, Greedy Treasure Seeker - not only do you ensure the character lives longer, each location will also grant the character the opportunity to quest for an extra lore
Aetherworks Marvel lets you pay six energy to cast a free spell from your top six cards
Mill is a very popular archetype in EDH, and The Water CrystalThe Water Crystal fits perfectly there...And that's probably its only home
Comparing the top of the A in Magic on the back of the card will also help