How can you not fight the mechanics?
I got in a battle with an Atlanta one night, while I was in a Bayern. I could not hit the Atlanta. Every round missed, while none of his rounds missed. He gets 3 cits and before I know it, I am dead and did zero damage to him.
So I go to our squad and tell them about this magnificent cruiser which has zero dispersion. We all get one and we cannot hit anything. We get decimated, game after game. They all but called me a liar and damn near kicked me out of the squad. The only reason they did not was another squad member came up against an Atlanta and suffered the same fate I did.
Tell me how that is fun?
What very likely happened is someone else citadel'd you and it only appeared to have been the Atlanta, this is guaranteed if he was using HE. As for Bayern, she is not known for accuracy, none of the KM BB's are. Even Scharnhorst, who has the best accuracy of the KM BB's, isn't that accurate. It is really noticeable if you are trying to hit someone who's bow/stern on to you.
Hitting things with Atlanta, especially at range, requires a good amount of skill in aiming to do. This is more obvious against fast and/or nimble targets. This is a common mistake for a newbie Atlanta player. They see her wreck house in a match and/or get wrecked by one, go and get her themselves, only to get punished badly trying to treat her like any other cruiser. She doesn't play to your style, you play to her's.
Mind you the following is fairly old, but it will at least give you a basic understanding on HOW to use Atlanta:
BFT is the most critical skill you will want on her. The rest is up to you, though some will be obvious picks.