I imagine the bites hurt, but I was once advised not to pull your hand away. The bird learns biting "works" if you do. If you don't react, then they learn it isn't going to get them what they want, or want to avoid.
You can add perch sized rope to the cage for her to climb on. I run strands across the inside of large cages, sometimes from a perch on one side to a perch on another side or from one level to another. You could add one of those spiral rope swings to it, in an area with a lot of open space. Sometimes I add branches for them to climb on.