You noob. This is not a suggestion. Its a pointless noob rant.
There are only 3 ways of making good credits.
1: CV- Fighters, shooting down planes
2:AA- Shoot down planes
3: SELL CRAP.
Its as simple as that you noob. You are not supposed to make alot from BBs, CAs, CLs, and DDs because they are CHEEPER than CVs.
Meaning you dont need as much credits to get the next ship.