I will say that I had similar feelings about Epcot and it has grown on me. I liked DHS instantly and Ak as well. But Epcot was an acquired taste.
In general, I do not do WDW like I do DLR. First, you of course need more time at WDW. Take two days for Epcot.
As I have said many times around here, DLR vets are more park centric and WDW vets are more resort centric.
Here is how I approach WDW including Epcot:
1. I take in way more music and street shows - these are in abundance at Epcot and especially World Showcase. My favorite is Off Kilter. Have you seen them? Last trip I saw them like 3 times! The Chinese acrobats. British Invasion in the UK area (they used to be better and are not that good but worth doing once - I usually see them once per trip). I always see the Voices of Liberty at the American Pavilion and I usually end up tearing up. See the Fife and Drum Corp. Also the street performer in Italy is hilarious. The street performers in the UK area are also very funny.
Seeing all of that takes a couple days. I do wander into the different pavilions when I have time.
2. And then the WS dining is cool. I have hit almost all the WS restaurants at least once and usually hit 2-3 each trip. My favorites are Canada (Le Cellier- hard to get - I have eaten there twice), Mexico (very good Mexican food for a place in Florida - I grew up in SoCal and know what I am talking about), and the food in the Italy pavilion.
3. See Illuminations - not my favorite show but it is cool how they tie it together with the whole WS
4. Plus just take in the beauty of the park and the plants and trees and water.
5. The Future World part is interesting too.
6. And then hitting Beaches & Cream coming out of Epcot at the Beach Club is something we usually do. Very fun.
7. Plan an evening where you take off from parks and watch a movie on the lawn there at the Beach Club/Yacht Club area. I have not seen an outside movie there but I have at Fort Wilderness and it was very fun.
8. Outside of the Epcot area, take in the rest of the resort. Go to the water parks. Go see Hoop-Dee-Doo Review. Go eat at Whispering Canyon. Or Boma's. Listen to the African storyteller at the Animal Kingdom Lodge. Slooooooow dooooown over the pace you set at DLR. At DLR we always seem to be on a sprint. At WDW we really slow down the pace.
9. Go on a tour. The Backstage Magic Tour is awesome!
Hope that helps!