Great to hear that the boat is back home--Bill touches on a subject which is important to me. The design of the boat, as well as the quality of the construction are important. If I was taking a small sailboat on a real adventure--there are only a couple of them I would choose. Certianly the Flicka, and some of the sisters from Pacific Sea Craft would be on the top of my list. Another boat would be the Francis 26 by Chuck Paine. Another really outstanding boat is the "Teak Lady" These were bult in Asia in the late 30's (Japan vs China) entirely, except the mast, which was spruce, out of Teak--copper riveted construcion. At least one sailed to Hawaii and there seems to be good evidence that one crossed the Pacific--these are only 18 feet long! One boat which caught my eye many years ago (as the C Dory did) is the Nor'east 27 by Lyle Hess. At least 4 of these have made a circumnavigation and there are over 160 Atlantic and Pacific Crossings!--Pretty impressive for a boat only 8'6" beam which is easily treailerable.
The San Juan 28 is a performance boat--and although capable of making the loop, it has several disadvantages. First is the fin keel--with a draft of 4' 6", and second the spade rudder. These are great for performance--and the boat has a PHRF handicap of 168, similar to a J 24, a Newport 33 and faster than a Catalina 30. Any boat can have a tabneracled mast--but the ease of taking the rig down is important. (I had a 45 footer with a 60 foot mast which a single person could take up and down in several minutes to allow passage under a 15 foot bridge. The other potentail weakness of this specific boat is the history of leaking hull to deck joints and chain plates. She is a light vessel, with 50% ballest to displacement ratio. (Yes I have raced on a San Juan 28) Because of the 10 foot beam, she has a very nice interior with more room than most boats that size.
For the loop, if I was doing it in a sailboat, I would more likely consider something like a Brewler Nimble or Kodiak. Not as fast, but a solid sailer with a pilot house. You have shoaler draft, probably an easier tabernicle system, and a long keel vessel, which may do you better in heavy weather. Despite Bill and El's sailing the majority of the way, most of the sailboats we see on the loop are motoring....Even in good sailing weather. Consider often narrow channels, locks, shoals etc.
Good luck and keep us all posted on the sailing adventures.