IJN Has one of the worst fighters for CV so FW'ing isnt gonna work unless you have really good fighters.
Set-up should be 2-3 Fighters and rest are DBs. Bombing CVs first in GBs should be your priority. Only send fighters if you need to scout a certain region, Escort your DBs or fend of Fighter Whores.
It wouldn't be Ideal for BB crew lvling unless you only need to level 2-3 sailors for amagi.
Do your best to avoid fighter combat unless you know for sure you can take out the figthers without taking too much of a loss. Taking out scouts and Taking down enemy CVs as I said should be your top priority and bombing other ships should come later.
Remeber that you aren't a God like a Tico, so you aren't going to win most fighter engagements. You only scout for your team if your BBs are getting fighter camped.