I entirely understand the point about going to too many places in a short amount of time. I have traveled like this and while I enjoyed seeing so many places there were times that I felt a little overwhelmed. Not so much from tiredness, but just mentally keeping up seeing so Much. In a way the amount of stuff to do is what invigorated me to keep going. When I would find myself in a city and realise there was not much to do is when I would feel tired and sort of let down.