Have you priced internal Peru flights yet? You might be surprised. This year a record number of tourists have already visited Peru and the height of season hasn't even hit. I also read that they will be reducing the number of visitors allowed to visit MP in the future (how near I don't know) That said, there are lots of new properties being built in the Sacred Valley. Have you seen some of these?
Peru Five-Star Hotel Deals | Luxury Link
Friends highly recommended Urubamba as a side trip, as well.