A card like Bound by Moonsilver, which stops a creature from transforming, won't stop meld from working
Prevent alpha strikes If you anticipate decks that go wide (ex.: elves) and you have nightmares featuring Craterhoof Behemoth, it might be worth slowing down combat
Flittersprites collect unusually valuable things: coins of fallen empires, baby teeth, and memories of treasured names
Marketback Walker is a nice early to mid game play in a counters deck, provided you have a way to sacrifice it later to cash in for a hand refill
Erikas Invitation full art card sells for approximately $260 loose, but can fetch closer to to $1,000 when graded a 10
For those unaware, the long and short of it is that cards that are printed in Commander precons tend to see more play than cards that don't