In black and green, the options for creature recursion and sacrifice outlets are numerous, so consider Gravecrawler or Reassembling Skeleton, or cards that are already mutants (and believe me, we expect more) and think of them as draw two cards when they die
You can count on prices dropping a bit, but it's a dangerous game to assume that they'll continue on a downward trend indefinitely
Youll want to wait until your opponent has a big monster on board so they have something good to swap with
Commander would be a better place with more aggressive decks, and these incentivize players to get more aggressive
Damaged (writing on back of card)
Cards in your sideboard can sometimes be accessed during the game, including game one, by using mechanics which search for them outside the game such as Learn