It sounds like you have done a lot with her set up to try and please her.
You don't say what species she is. I'm guessing a dwarf by the wheel size. The only thing I can suggest is to add more bedding so she can burrow. If she is a chewer you could add cardboard/grass mats to the outside of the cage so they don't get destroyed and the bedding doesn't fall out and make a mess everywhere.
This is a video i did about getting more bedding in a barred cage- hope it helps.
More bedding in a barred Hamster Cage | Cosmic Hamsters - YouTube