The card is gorgeous, with deep purple and blue hues, intricate frame breaking, and it's a high rarity card that's highly playable as well
Speed comes from consistency in the first three turns, so having a high volume of these creatures provides the damage these decks want
MTG Flash Decks Flash is most common in blue, black, and white
Having to start your engines early while setting up haste later in the game are both keys to winning
Raffine is a brilliant Esper reanimator commander, offering an unattractive engine target thats always worse to hit than whatever youre putting in the yard to bring back
If you want to talk numbers, Id say 8-10 pieces of mana ramp is a good number to aim for, but thats very arbitrary