I really liked Guide Mike, for his explanations about the culture, architecture and history of the city, without going into details such as politics and religion, as he highlights in his presentation.
The tour is very complete, covering the city's main tourist attractions, contextualizing the historical issue.
The top, despite the cold, is the best option for the tour, as regardless of which side you sit on, there is something to see. But I think the right side of the bus ends up being more beneficial.
One suggestion is to do the entire loop and only then start descending at the points. It's difficult to go to all the points in just one day - impossible, I would say - but with the tour it is possible to identify points of interest and the distances to cover them. The center of Philadelphia is easy to explore on foot, my second day was made easier by the tour the day before.