I'm not exactly sure what your daughter is going through, but mine has no developmental issues and I use toy rotation just for the sake of not having to buy new toys. If I put up certain toys for a few months, when I bring them out it's like they're brand new! Much cheaper! lol
Well...my daughter was a bit spoiled. She has TONS of toys. I leave out most of the little stuff. But the bigger stuff I rotate every 2-3 weeks. I leave them put up for about a month and she completely forgets about them and is super excited when I bring them out!