As my bunnies aged, by the time they were five, they were able to free roam because they were less destructive. When they were younger, I did have to limit their time out – they had large pens, but then they would get exercise time throughout the house while supervised. (usually at least five hours).
But you said your bunny can exercise in your bedroom, hallway and partial den? If she is able to run freely back and forth then that is good exercise unless you live in a box.
But if you want to allow her more room in the den, it shouldn’t be too hard to bunny proof, and that way you could enjoy each other even more. I even had our xbox controllers bunny proofed (but now they are wireless so I don’t have to worry anymore).
You can use the xpen to block off smaller areas that allow her more room instead of using the pen to confine her.
let us know what works for you.
If you need help with bunny proofing the den. Whatever the major issue is, I bet we’ll be able to find a solution. (crossing fingers)