1

When you say "cross-country," you imply you are traveling across the country.
xFlorida is a state. Crossing it is not "cross-country."

I have no idea why you are spending seven nights in xSarasota.
But I will assume you'll get around the xTampa area in that time. That includes a trip to Myakka.

The best "scenic" spot is something you already pass on your way north--the xEverglades.

Head to Ocala. This will probably be your best chance to see non-swamp xFlorida. (Ok, there are still swamps, but not as much.)
After that, get yourself to Canaveral for a day. NASA is right next door, if you're so inclined.

2

"Inland" central/south Florida is not "tourist" Florida outside of Orlando. It is swamp, table produce, citrus groves, and a few open pit phosphate mines mixed in for variety. If you like to fish, you may want to visit Lake Okeechobee. Be sure you drive the Tamiami Trail across the peninsula in at least one direction on your trip. It is best just after sunrise or just before sunset. Otherwise, I can't add to Bzookaj's suggestions.

Enjoy your stay.

3

Unless you head all the way up to the Orlando area and then back down, and there really is no reason to go to Orlando unless you want to visit the Disney area or play some PGA golf courses, there is nothing as your drive across the state...not the country...Why are you going to Sarasota 7 nights? Is this Spring Break?

You already asked about the Everglades/Miami areas and what to do, was there something you didnt grasp?

The drive from Miami to Naples is a long hot flat road thru plantations of endless nothing.

4

Solohobo, have you ever driven the Tamiami Trail?

5

No, just 75....

6

You should visit the Everglades either on your way from Key Largo to Naples, or on the way back. Take an airboat ride, stop at big cypress nature center. Check out their website to see if they have any ranger led programs while you're there ( the wet walk is phenomenal) They also rent canoes. Stop at shark valley for a nice bike ride (i'm pretty sure you can rent bikes there if you don't have one). Also, check out Clyde Butcher's studio in the 'glades- a famous photographer who takes stunning black and white photos of the everglades.

If you do go north, Ocala national forest has a great one day canoe trip.

7

First, be aware that airboats are illegal inside the national park. Any legal outiffter will take you in the surrounding swamps (which is still the "xEverglade").
Second, if you want to take an airboat road, I suggest doing it at xMyakka instead. It's not as environmetally destructive like those in the 'glades, since it operates on an open lake.