Dealing with the roads is one thing, dealing with the drivers another, but maybe it won't come as a shock, compared to where else you've driven. Brazilians, known not being in a rush or short-tempered, change when they drive. Learning some Portuguese phrases in case of an emergency, or even just getting lost, would be helpful. Makesure you have adequate auto and health insurance. I'm sure you know fuel prices are high. I can't imagine what the price would be for such a one-way rental.
Small thing: in the city of Fortaleza, if you have an accident, even a minor one, you're supposed to keep your car where it is-- even if it blocks traffic-- until traffic authorities arrive. Only city with this law that I'm aware of.
Good idea to be planning on driving only during daylight hours, due to safety concerns (accidents and robberies). A few years ago, we drove from Fortaleza to Natal and back, and survived.
Boa sorte!