Hey there,
You need to keep in mind that once you get north of West Palm Beach, you enter a very different "culture" within the State of Florida. South Florida has some great things to do, but from a scenery standpoint...you can do a lot better...especially if you aren't into the entire South Beach type of scene.
There are some amazing sights along both the east and west coasts, but you'll just need to lay out what you really want to see. Orlando is going to take you about 3ish hours to get to. If the numbers work, it would seem a little counterproductive to drive up to Orlando or Tampa then drive back south if you can avoid it. Besides, gas is cheaper once you are out of South Florida.
Sure that you've seen it, but
www.visitflorida.com has some great resources you might want to look at.