Took a 3-night Baja cruise with my family (wife and kids - ages 12 and 18) including one day in Ensenada and one day at sea. This was our first trip on the Disney Wonder after having sailed on the Dream and Magic in the past two years, respectively. There are some distinctions, which I will summarize below.
1. San Diego port - easy to enter /exit logistically, perhaps even more so than Port Canaveral. The presentation is underwhelming as this is a Disney rental/lease arrangement and it is apparent that Disney is a part-time tenant but they do their best to extend the Disney welcome to passengers. If you've been to Port Canaveral and experienced the grand Disney entrance there first, just lower your expectations accordingly and you won't be disappointed. Aesthetics aside, I found the efficiency of boarding/leaving the ship in San Diego to be preferable.
2. Cleanliness/Appearance - the Disney Wonder is immaculately presented, especially for a ship that is 17 years old. If you look hard enough, you'll find evidence of wear (i.e. tiny rust marks in shower corners) but these will all be addressed in its forthcoming refurbishment and nothing takes away from the current day experience.
There has been much debate about whether concierge is worth the expense on the "Classic" ships. The single word answer is: Yes. Despite not having a designated Lounge (which is rumored to be forthcoming after the late 2016 Dry Dock), there were plenty of concierge receptions each day and designated benefits. Furthermore, the concierge hosts on the Wonder are as good, if not better, than the hosts on Disney's other ships - and that is a bar that is pretty high. So my recommendation is to go for it!
Logistically efficient though aesthetically underwhelming.