We loved staying at the Dolphin and would readily do so again. It doesn't have a specific time or place theme like the moderates or deluxe resorts do, but they do have a whimsical style and architecture that makes them unique and enjoyable in their own right. It's more like staying at the contemporary minus the monorail. The rooms were great, the beds were amazing, and there are some amazing restaurants in the Swan and Dolphin complex. You get all the perks of staying on property except being able to charge purchases to your room key. You get extra magic hours, You get disney bus transportation (same bus line as yacht, beach, and boardwalk) or friendships to Epcot and MGM. You can quickly walk to boardwalk, or take a bit longer hike to Epcot's back door. Disney Guest Services is also missing so it's a little harder for the front desk to help you book dining reservations, tours, shows, etc. The only annoying thing is they keep telling you they aren't a Disney resort whenever you ask them a question.
We've also stayed off site at both on hotel plaza blvd and other orlando area hotels. When you are off site, you're offsite. Even with the shuttle buses we found it much easier to drive ourselves onto disney property. It was never really practical to come back to the room for a mid afternoon nap. But we got a nice comfortable room for a lot better price. So it's a trade off.