You're right that basically every team plays swarming D. I think you're best bet is to stay on Professional or move up...no reason to play at a difficulty where you have no problem scoring. The key to improving at those levels is to pass more (and probably at closer distance) and not dribble/sprint too much directly at the defense.
One thing that helped me a lot with the through-ball and attack in general was playing with two strikers (or a ST and a CF) - you can play the one-two between them which confuses the CBs since they're split.
Another thing is to adjust the tactics to how you want to play. I play with heavy short passing and then increased shooting and less crossing in the box, and once my tactics matched with the Custom tactics in the menu, my offense improved dramatically.