I just came home from a trip that I tagged along with my friend while she was at a conference. It was just the two of us, no husbands or kids. We spent four days in the parks, one park each day but didn't start some days until the afternoon due to her conference. We went during F&W so I'm glad we did Epcot, but really...it kinda has lost its luster to me. With all the changes in AK and DHS, they have edged out Epcot for me. With your partner being a newbie, I say MK, AK, and DHS. Pandora and TSL are just too awesome to miss and Epcot really is going to be the same (except the Frozen ride) as when you went last probably.
Good Luck!