For your set up, i would reccomend 6 fighters and 2 bombers of your choice
(everyone carries bulge these days because of subs, so with most ships DB is the
best way to kill it). This set up will give you the ability to defend your side or scout
the enemy (if you choose to do so) but if you have to run you still have a way to
attack. This is a pretty versatile setup, but you can mix it up if you like.
For gunners, youre going with US cvs so i would reccomend it. But buy them or level
them up later on, when you start out youll need every slot available to level pilots.
Same thing with seaman, he is useful for your fighters but you need to have every
slot filled in your lower level carriers with pilots. Yorktown will be the first to carry
gun slots, but even those should have pilots as well. Once you hit lexi youll have 8
supports, so you can start putting new elements into your crew (such as the
gunners on the lexis gunslots, or a seaman and support).
If you decide not to run gunners, youre going to have 2 open slots on that midway
and tico. You can use reps on those as reps will work on gun slots, and so do
restorers (dont use them. Theyre not as useful as reps are for a cv). Youll also have
9 supports, but only 8 pilots will work in them. So you have an extra. This would be
great for an engy since they have to be in a support slot to work.
Overall youll have 12 slots on your midway.
8 (or hopefully 8...) pilots
2 gun slots
an extra support
EDIT: Forgot to mention, seamen work on the gun slots as well.
Hope this helped, and good luck.