I'm not sure about your offset problem, but it may be worth opening the stick and ensuring that everything is in the right place. It's not a complicated piece of equipment and very easy to piece back together.
There are no force feedback effects in the choppers as far as I know, other than the centre force.
The steps are apparent on my own FFB2, although I've extended the stick and it's now far less apparent. I was previously borrowing a FFB2 from a friend, which had much less noticeable step feeling, although internally the sticks looked the same with no signs of wear, I suppose it could be the motors or some slight revisions in the circuit.
My advice is to turn the force feedback down as this will significantly reduce the jerk when setting the trim.