Well my complaints are really as follows about the default A321:
1) Controls feel too light for my liking.
2) Wont come out of a turn easy.
3) Rotates at 100 KIAS even with full load
4) Lands at about 80 KIAS with about 3/4 full load.
5) Seems entirely un realistic from the A321 I flew on in real life.
6) Speedbrakes have too much affect on lift and speed.
1) That's the "fly by wire" ... try turning off the flight augmentation. If you mean that the A321 responds too quickly, that gets into MOIs
2) Again, the flight augmentation computers (the shut-offs are on the overhead panel)
3) It rotates, as in the nose will lift at just over 100kias, but the wheels will not lift until nearly 135kias (all very close to realistic)
4) I had to turn the flight computers off to keep the auto-throttle from kicking in, to even get it to slow to 130kias.. with full flaps it stalls and fall out of the sky at 115kias.. I have no idea how you got it to land at 80kias
5) I've never piloted an A321, but I am a pilot... if you fly the A321 by the numbers, it's pretty realistic
6) These too, seem pretty close. They bleed off gobs of airspeed without serious pitch.
I'm not doubting that you don't like the way it flies, but I'm guessing you aren't flying it by the book. It's two completely different airplanes with the computers on or off. Also... I have my realism settings on the most realistic (most difficult) setting. Set on "easiest", they very well might allow you to stay airborne at 80kias.. I have no idea. We could be flying completely different airplanes.