KSC is fun for a couple of hours, for space buffs. If you're not a space buff, you might reconsider KSC. Personally, I love it.
My MIL lives in Cocoa Beach (getting ready to move up to Ohio). The beaches there are terrific. Try to go to one slightly south (2 or 3 blocks maybe) of the city hall, etc. Quieter beaches there. Of course, Cocoa Beach is just south of Cape Canaveral, where you can see the Disney boats, and other cruise ships certain days of the week.
For shopping go to Merritt Island. There's an ok mall there, and a bunch of strip mall types of places. Next to Merritt Island is a little place called Kiwanis Park, where there's a lot of outdoor activities, such as basketball, racquetball courts, etc. I'm a Kiwanian so I need to promote Kiwanis park! There's also the Pier in Cocoa Beach, on the north end of the town, with a few restaurants, bars, etc. and Jetty Park a little further north.
It's not WDW, but Cocoa Beach is definitely a nice quiet day at the beach if you're looking for that.