For a while, I've tried to think of ways of dealing with ships that either have good AA (Texas, higher-tier USN BBs, RN CLs) or have DF ability (Cleveland, Atlanta, most other cruisers.)
Here were some:
Find out how long DF abilities for different nations last, and cooldown. I watched a Saipan replay where the guy sank a Pensacola, when the target's DF cooldown was on cooldown. Another tactic would wait till later in the game, when they've likely used them up (except for Atlanta, which gets unlimited cooldowns.) For higher-tier CVs, I'm going to try and feint to them earlier on, to force them to burn their one and only DF for the round (unless they get two.)
For ships that don't have it but good AA, waiting till late in the game is a good strategy. I watched a Grosser Kurfurst replay where the guy survived, but was sunk by dive bombers. Jingles said the ship has an AA rating of 100, but it's not any good after it gets shot up quite a bit, and a lot of AA guns are knocked out. If said ship has near full HP, then call up your teammates to do it, unless they are that incompetent, like most teams I get placed on. In that case, the best idea, at least in my opinion, would be to just go for broke and launch an all-out attack to swamp the AA. If you have the clock running down, and your team is behind on points, you have nothing to lose. Then again, RNGesus might be a bit nice, and grant you some lucky detonation or something.
Those are just my ideas, which might sound dumb, but then again, something's only dumb unless it works. I'd like to hear yours. Thanks!