CV6 is only 12 slots

after your 8 pilots you got your BO and perhaps a Seaman.

If your seaman is a fighter+restore seaman, you would have hit 900 SD by CV5 if not earlier

The other 2 can be 2 Gunners or any combination of Repair or Engineer.

I would suggest Leveling 2 more Ftrs so you have some more flexibility in your cv setup.

Should the gunners stay gunners or class to AA?

For US gunners, rld-rld-rld gunners will work fine and you can use HH if you desire or even use them on a BB later on

reason is because US AA guns are the same or worse than regular guns unlike other nations.

So reload gunners make the best AA for US?
Also is 11 fighter stat Ok for my fighters?
I don't really feel like rolling all day for 12s.
Or is it a must?

yes.

AA gunners have access to A variant guns, but lose the ability for to use regular guns and for some nations, HE and AP shells.

For most nations their AA guns are superior to regular guns like KM or IJN so it is worth it but for US, the guns are pretty much the same.

Also for US, when you class as Rld>Rld>Rld you gain +4 then +3 then +2 in the reload ability where if you class 2nd AA>1st AA>Chief AA, you lose reload ability. So obv the first route gives you faster reload.