Youngster certainly sounds interesting, but all the current options are rather lacklustre.
I don't see Expose being good at all. I would have no hesitation attacking the 2 agility Tie without defensive tokens over the evading Howlrunner/Youngster. And Tie's would find it difficult to 'get into a safe fireing position' to expose, while also being within rage 1 of Howl AND not being able to use an action to arc dodge AND are likely PS 1.
Expert Handling doesn't really protect against alpha attackers as most target locked ships will have moved before the lock takes place.
Marksmanship suffers due to the Tie's only having 2 attacks, but could be good on some named pilots.
Daredevil would be amusing, and is probably the best option for the generic swam (but still poor IMO). Every ship having a potential pseudo-boost upgrade would have uses.
Squad Leader is just too limited, with little gain.