Though more common today, older reverse holos steadily gain value over time
This is sometimes the biggest trap for players coming from the Yu-Gi-Oh
Aegislash does have a lower Speed, so players should try and alleviate this as much as possible with the move Automize
Plus, it's a Warrior, and RotA is @3 now
You either need a deck full of giant creatures (Ghalta, Primal Hunger) or creatures with big bodies that are balanced with drawbacks (Death's Shadow)
Another thing I heard from many of the people whom I spoke to was the importance of limiting the number of copies of cards in their collections: Jesse Lyons from Castles and Cooks and jestergoblin: I generally keep four of each card with the exception of staples, like Brainstorm or Counterspell, where I have around twenty copies. Adam Styborski from pretty much everywhere but primarily GatheringMagic and DailyMTG.com: I sell/trade most of my rares and valuable commons/uncommons