How old is the horse? In my opinion a wonder bit is to much bit for a green horse, have you tried just a simple d-ring snaffle? Any way to help her find her feet and balance I would go back to ground work and lunge her over ground poles at different heights she will have to get off her front end to get over them. I would also work on a lot of flexing side to side she has a stiff body and flexing will help her soften. Sticking her nose out to avoid the bit is a sign of stiffness, stop her with one rein so she cannot avoid the bit. You need to teach her to be responsible for her own feet let her walk on a loose rein if she trots sit down deep lift one rein flex. When she will stay at a walk on a loose rein then ask for a trot on a loose rein if she gets going at a fast trot let her until she slows down if she breaks gait sit down one rein stop, flex her. When she gets good at the trot on a loose rein ask her to lope let her lope on a loose rein until she slows down on her own if she gets to fast for your comfort sit down one rein stop, and flex ask again for the lope. She needs to learn how to balance a rider and herself if you micromanage her feet she will never learn how to do it. The key to good vertical flexion is lateral flexion. Work on getting her soft through her entire body head and neck, front end, rib cage, hind end and the balance problem will fix itself.