I meen not heavier shafts, but heavier swingweight now i`s D2!

.I wouldn't see how a heavier shaft would improve the location of your ball impact...I've heard of people who swing on a steep plane having a higher ball impact...Sounds like you might need to flatten out your swing. I could be wrong, but making a shaft change doesn't sound right to me.

Personally I tend to hit the ball lower on the face or thin when the shaft is lighter, but that all depends on the person, sounds like you need to change you angle of attack, I suggest going to a local Professional and having him or her make sure the clubs you are playing are right for your swing in terms of shaft (flex/weight) and length and lie. If there isn't anything major there then you need to make some changes in your swing. 

Try getting fitted and see what you should be swinging, then have your current set looked at.  Might need some adjustments to the sticks.

Roman

Choke up on the club and keep your posture the same