The reason that Ive opted to not include legendary angels is that it would be all too easy to fill up the list with popular commanders such as Giada, Font of Hope or Atraxa, Praetors Voice
Extra ramp like Cultivate and fetch lands like Evolving Wilds let you surprise opponents with sudden boosts
I know I'm still trying to sneak a Scuttling Doom EngineScuttling Doom Engine into every deck I build, and it'll probably make the cut one of these days
Her ability to play a spell from the graveyard once per turn gives you plenty of options throughout the game, and she can often run a number of combos to overwhelm your opponents
This means you could spend the mana to activate an ability of an artifact you control or an artifact card in your hand or graveyard, for example
Pushing the impactful cards to higher rarities helps make the games more even-keeled in Limited because of card as-fans (the rate at which a certain card or subset of cards show up within an average booster pack) and in casual Constructed because of card availability