Just to add my two cents

... My family and I have stayed at both the Dolphin and the CBR. We like both of them, but the Dolphin is our first choice!
We prefer the Dolphin because we like being close to Epcot and DHS and the other EPCOT resorts. Being in this area brings us close to a large variety of counter service and table service restaurants.
We like taking the boat to DHS and EPCOT. I honestly do not think I have waited more then 15 minutes for a boat and the norm is usually five minutes. We have walked from the Dolphin to EPCOT but I have never walked to DHS. The walk to EPCOT is about 15-20 minutes, but my DD and DS were teenagers when we walked. We also stopped at the Boardwalk Bakery for our Breakfast which we ate walking and laughing along the way. I have never walked back from EPCOT because my feet are just way toooooooo tired! My DH has walked back and he loves it!
Regarding the International Gateway entrance. I used to think of this as a negative when I wanted to get into FW, especially for Soarin' or Test Track. But, we send our fastest person on ahead and we have never had a problem getting FP's for either attraction. Also, talking about straight walking...If you consider the walk from the busses to the main entrance at Epcot and then the walk over to the land or Test Track...it may be even longer then the walk from the boat over...I'm not sure....I never measured it....but trust me....you are walkin'! for both.
We also like the feel of the hotel vs. motel...now don't misunderstand the CBR is not a typical motel...it has a great main pool....terrrific theming...and nice food court....and nice rooms...but we prefer the door to open inside to a hallway vs. outside.
The rooms are larger at the Dolphin and for us we like the extra room. We also prefer the pools at the Dolphin as well.
On the flip side, I also have NEVER had a problem with bus transportation at CBR. I think I waited an average of 10 minutes for busses.