My friend got the new Epic kits, but I haven't (yet), so I'm trying to learn the rules as well as I can from the references alone.
If I understand correctly, Wings are all about movement. I see nothing inherent in Wings pertaining to shooting, other than the ability on the Wing Leader card(s). As such:
1) Ships in a Wing shoot independently, just as normal. Each Engages and chooses its own target separately, again, as normal.
2) Ships in a Wing are targeted separately, just as normal. There is no such thing as shooting "at a Wing".
With regards to Wing composition, the wing leader cards I've seen only specify ship type , but no restriction for any individual element to be named or generic. So:
3) Wedge's wingmen could be 2 generic X-Wings, or they could be Luke and Biggs
4) Likewise, Luke could have Wedge as his wingman
5) In such a case, the wing still activates at the initiative of the Leader (e.g. Luke), even if a wingman is higher
6) ... but they also Engage at individual initiative, so Wedge will shoot before Luke
Please correct me on any I got wrong. The rules reference seems pretty clear, but it does run counter to how I assumed they would work, based on other wargames.