Attacking goes with pressing whole peach, not you'r own half.
You'r team is fine, trophy room says enough.
You may try to get a def wall and aerial defender aswell.
I personally find a playmaker in the middle pretty useful also :P Many people say its useless but it's still worth trying to powertrain your 4Stars MC.
good luck
p.s: Cup is mostlly about luck.. You may try to get you'r team down to 4Stars and then re-build it back to 5-6Stars in the begining of the season but that won't guarantee you success