Easto, your issues are classic beginner issues. I suffer or have suffered from all of them. Ideally if you could get someone to take a video of you riding, it would help you a lot. Next best would be to get a camera on a pole and video yourself. Failing all that, you can "feel" yourself doing all these things if you concentrate. You need to be on a non-challenging run so you don't have to concentrate on the terrain. Then just feel yourself doing heelside turns, for instance. Vary your lean, vary your turn radius, vary your weight distribution. See how the turn changes. You'll zero in on what works better.
Or you could just always pay for a lesson with a more advanced instructor. Give him specific instructions as to what you want to work on.
Coffee is your friend. Everyone else is an acquaintance.