I will be in that situation in May. We plan to stay at the Yacht Club and have dinner at Shulas, followed by a night at Jellyrolls. Honestly, my first choice would have been Yachtsman Steakhouse, but this is DH's pick this time.
We will have a night out over the summer when we travel with family and YSH will be my choice then.
If it were me, I would definitely do Epcot. And I would eat at a World Showcase restaurant....either 9 Dragons, Teppan Edo or Biergarten. That would be one perfect Disney Day!!!
I've done that a couple of times when I added a day to a work trip. I have an annual pass and usually hit at least 2 parks. The last time I did DHS and Epcot.