Greetings from South Carolina Bryris

First thing that I would suggest is that you have someone that is a Instructor properly trim your G3 settings for training purposes.

Next try holding your stick with your thumb and forefinger, as you make any movements, all it takes is slight movements from the center. Just like when you are flying your trainer, all it takes is slight movements.

The resistance of the spring tension should be the same no matter where you hold the stick.

The accuracy comes from practice of doing any maneuver over an over until it becomes second nature.

When you speak of rolling out of a steep turn, the airplane will climb and you have to give it down elevator, 1st of all when you make a turn it is best to hold slight back pressure on the elevator while turning so that you keep the airplane from loosing altitude. If the airplane climbs then the airplane is either out of trim or we are applying too much back pressure on the elevator or the wind is causing this to happen.

Same thing on final approach, our airplane / and or G3 has to be properly trimmed for hands off level flight and our stick inputs have to be slight.

I hope this makes sense, it sounds to me like your G3 is not trimmed and you have to chase what inputs you give your radio therefore the settings are too sensitive and can be adjusted more to suit your stick movements.