Dismiss Friends & Resources:
The Horror! The Horror! (event)
These cards can collectively allow you to diminish your opponent's Friends and Resources.
Back from the Dead!:
Rarity, Nest Weaver (Friend) x2
Golden Gavel, Fast Talker (Friend) x3
More or less, this is Fluttershy's ability with Caretaker and Critter Friends
Lemon Hearts (Friend)
Eagle, Soaring Raptor (x2) Raccoon, Scrounger (x2)
And finally Doctor Horse, M.D. (Friend) x3 round out this section of power-ups nicely.
Power-ups to meet Requirements:
Initially it might seem that there are a fair amount of secondary colour (Diamond - white) cards that could prove difficult to get into play. However, these following cards are awesome at powering up for the Main Phase in order to get those pesky requirements met and into play!
Coco Pommel, Fashion Apprentice (Friend)
Octavia, Star Cellist should be accompanied by Private Party (Resource) x2.
Which brings us to
Attitude and Pizzazz! (Problem) x2
Although the Celestia deck may never be able to play all these strategies at once, there's no reason why it can't be extremely versatile and toggle back and forth, never letting your opponent know where you're going!