I literally just got back from Quito today. I flew down on Friday night, partied that night, then woke up early on Saturday to climb Pinchina, we made it 14,200 ft before we got exhausted. Came back and took a bus to Mitad del Mundo, had dinner, then caught the 1030 back to ATL.

I'd say you only need two days to see the "major" stuff.