Caracol is best done with a guide or in caravan. It's a remote place, no cel reception and if anything goes wrong you are very vulnerable.
4Wheeling is fun in Mt. Pine - I also caution you (cause we did this) to take the main routes and not even think of going off track. There are so many little logging roads that seem to go someplace - but where? It's very easy to get lost and you cannot call for assistance.
Agree that the Hummingbird is incredible. Really incredible. Heading south to Toledo is a remarkable drive as well.
Avoid night driving - there are places where the roads go over culverts and have no safety rails on the sides. These passages tend to be narrow and if you misjudge it can result in a bad accident.