It's a tie between MK & Epcot, although Epcot is slipping into the lead by a hair.
I love the wide range of different experiences I can have in Epcot - I love the atmosphere, the details..... I love the little shows & performers. I love to SHOP! I love the dining. It's a place I can go & never ride one single attraction & still have a day filled with enriching & fulfilling experience.
This doesn't mean that I don't still love MK & hold it in a special place in my Heart - I love the atmosphere, experiences & joys found there also. It's just as time goes on & I have spent more & more time in all the Parks, Epcot has just moved a tiny bit into the lead......