Solid Hardwood, Engineered and Laminate Flooring - Pinnacle hardwood install ?

I talked my wife into installing hardwoods in the attic that i am finishing, question is this room has 3/4" plank subfloor and I have allready pulled some up and shaved the joisted where there was a ridge in the middle of the room, most of the flooring is pretty solid some areas still need some work where some edges are either slightly higher or lower than the surrouding planks, how critical is it to have exactly perfect subfloor when installing pre finished floors, I will be installing 3/4 x 3 1-4 flooring, I am trying not to tear out the subfloor any suggestions would be appreictiate, also wondering about acclimating the flooring in the attic before install I have a sepreate system to heat and cool but it is not hooked up yet and is 48-72 hours very critical. Thanks