Our most recent modification has been surprisingly successful...for now. But like all of the other ones, I don't expect it to last forever.
We took the barriers down and instead made a fort for our son. We still have an "older kids only" section but now it is inside the fort and out of our daughter's view. With her brother and the choking hazards more hidden, she is spending more time playing and less time attempting break through the barriers. Let's see just how long this modification lasts...maybe a week?