I am currently at LIM after finishing a Sacred Valley/MP/Cusco/Barranco trip with the wife.
As others have said, it really depends on how hiking extensive you guys want to be per time period. I did stay at Tambo del Inka and also Palacio del Inka, and highly recommend those as a SPG member (they gave me an upgrade as a gold member), and you will be treated very well.
Do get the extended tourist ticket to visit all of the sacred valley/Cusco sites
Things I would recommend:
1)Try to fly into Cusco early, and when you drive to Tambo del Inka, see if you can get a Sacred Valley Trip with negotiation with the taxi driver or a private tour guide (we hired Duptours.com, Sabino). This will save you a day. We ended up seeing Chincero/Moray/Moras/Salt Mines while heading to Urubamba (where Tambo del Inka is located).
2)I would look into seeing the Ollyantambo ruins when you drive back to Cusco as they are spectacular, having pre Inca stone work (perfect stone joints), face carved into the mountain...
3)Cusco: Palacio del Inka is right across from the Sun Temple, and you can walk to most museums on the tourist ticket. I would recommend hiring your own driver/tour guide for the surrounding areas so you could spend as much time as you want at each site. Spend extra time at Sacsayhumain as there are alot of areas to explore (natural slides, carved rocks away from the main site); 2 hours minimum. I would also recommend Tipon (one of the most amazing things in Peru is the Inca canal and waterworks; I wished I had more time to hike up to the source of the Inca canal)
4)I would try to convince you to stay at Barranco rather than MiraFlores (much more romantic than Mira Flores, quieter, and is safe). Depends on how much luxury you want, a boutique place (not super Luxury, but nice, and very well priced at 80-90 USD/night) is 3B Hotel. It is walking distance to art museums, romantic parks, ocean views...You can always get a taxi to MiraFlores (8-10 Soles) from Barranco.
Hope this helps, and enjoy Peru; its a great country with good people!