I haven't stayed at either, but, if the cost is the same, go for the Boardwalk. I think that the location is excellent for adults (Boardwalk and Yacht and Beach Club). You can walk (or take a short boat ride) to and from the back of Epcot (World Showcase). Epcot is usually the last park to close, and you can walk around the World Showcase, eating and drinking your way around the "World" (wine and beer are sold by the glass in the various countries, such as France, Italy, and Germany), watch Illuminations, and be back in your room in minutes.
You also have access to a huge number of restaurants (formal and informal) with Epcot, the Boardwalk, and Yacht and Beach Club within walking distance.
We honeymooned at WDW (WL) and went again for our 4th anniversary. On that second trip, we seemed to end up at Epcot's World Showcase every night, even if we spent the day in another park. It was a great way to end the day!
I hope that you have a great honeymoon!