If you fully insulate between the rafters as shown, you will have no ventilation and the heat/moisture buildup will destroy the roof. Vaulted ceilings are nice but you need to frame up one a bit below what your structure wood work is. Thereby eliminating the venting problem. At the eve, where the wall joins the roof line, a hopper vent tube must be installed to keep insulation from closing off the vented area. Common sense stuff. Mice are always a problem. Get a cat. Paul www.severngaspumps.com