I think there's plenty that can be done with the Y-Wing that doesn't include just an increase in it's primary attack.
The whole point of the Y-Wing in this game at least, and in XvT was a slow tanky type ship that offered control. I couldn't count the number of times my friend would blast me with Ion's in XvT then fly though my ship to destroy me...
So some of the things they could do is more turrets, perhaps a 3 dice blaster turret that only works on Y-Wings.
Cheap torps, which may make them actually worth taking on the Y.
Perhaps a recon upgrade giving it more support options, like a AoE TL, so every ship in range 1 gets a blue TL on the same defender. Maybe giving up the turret slot for this.
Giving up the turret slot for a bomb slot.
Reinforced shields that cause damage if the Y runs into another fighter.
There's all kinds of things you can do that keep the Y in the same role... Yet give it more options.
Edit: Oh and regarding the fluff... A early sketch had the Y-Wing, X-Wing and Tie Fighter all at about the same speed. The idea of the Y-Wing being a slow tanky type ship wasn't part of the movies.
Edited by VanorDM