Can Rey's Falcon pilot ability be used to support any friendly ship if the defender is in her firing arc? Does it mean 'you' as the Falcon only or 'you' meaning the player, therefore allowing her ability to support all friendly ships?
Rey's Falcon Pilot ability
'You' always means the ship.
It applies to just her. The "you" in a card exclusively refers to the ship that card is equipped on. It will specify "friendly ship" if the effect applies to another ship.
it's on page 2
CARD INTERPRETATIONS
Many Ship card abilities use the word “you” to refer to the corresponding ship. Upgrade and Damage cards that use the word “you” refer to the ship to which the card is assigned.