I'm interested in climbing the campanille, visitting the duomo museum, the cathedral itself and the baptistry. I know it's probably best to start with the tower as it's open early, but then I'm not sure how the crowds will be on the other sites. I plan to be there by 8:00 or so, on a monday in May. It would be interesting to know in advance what to expect in terms of queues.
Also what is the least crowded place to buy the combo ticket that covers every Duomo site?
Thanks!