Yeah... P-39/63 Yak-9T/K, KI-45, and certain Stukas... Learn to respect these planes, learn their advantages, their disadvantages, pay attention to them and NEVER LET THEM ON YOUR TAIL. Odds are, if you let them get good positioning on you, they won't need more than one shot.
None of them are all that maneuverable, but they're all great at hunting bombers. There's a good reason why you don't see all that many heavy bombers playing. As a heavy bomber, the only real counter for these sorts of planes is fighter cover to keep them distracted from you. But good luck ever getting that in a normal game.
Bf-109s around those tiers start getting really dangerous as well. Only 20mm cannons, but they can mount 2-3 of them and they basically have the best climb rate in the game outside of jets. You will ALWAYS see 109s up high either attacking bombers or in good position to boom and zoom planes below.
Bombers tend to be screwed, and the only thing I can sort of suggest is start practicing taking control of your turret gunners early, learn where and how you have to aim to hit enemies out past the point where you have an aiming circle. 1km is easily doable, I've heard stories of people getting hit out beyond 2km. Personally I can't really do much outside of 1.5km, but it does make them waste energy dodging your shots, which gives you more time in the air, more time for the hope of allied fighters, and more of your own shots travelling in their direction which might get a lucky engine or pilot hit. Otherwise sometimes your only hope is to find the nearest group of allied fighters and dive/run towards them.