That makes sense to me, it is very similar to the trip I made, a loop around central Portugal. My itinerary was Lisbon 3 nights, Sintra 2 nights, pick up car, Obidos 2 nights, Marvao 1 night, Evora 2 nights, Palmela 2 nights. Worked great for me. I will go to Porto and to the Algarve on other trips.