I think Orlando is a great place for retirees for the reasons you mention and more. Orlando is a cosmopolitan city with a home town feel. There are universities and colleges here, there is a Performing Arts Center, and lots of entertainment options. There are some great restaurants along with the familiar chain restaurants. In short, people from Northeastern cities should feel right at home here.
So why isn't Orlando on the list of "The 10 Best Places to Retire in Florida." Perhaps because Orlando, unlike the other places, is not primarily a retirement community. In fact, the age demographics make it similar to other cities. The demographic mix is what I like about Orlando.
On the other hand, if you want to live among retirees, there are plenty of 50+ complexes in Orlando to accommodate you.
And finally, as you said, you have easy access to a major airport. And you can thank Disney for the low fares. Orlando is a major tourist destination because of the theme parks located here and that keeps air fares low.