Short answer? 

 Does the level of detail depend on PM experience or complexity of the project or both?

 In what ways does a project baseline help to identify variance? What does the PM do with this information?

Do you feel that these challenges are what develop our learning and increase skills as PMs to be better at managing projects?

Do you feel that most projects have the same types of issues arise or are they unique to each project? How much variance are there between projects across industry, complexity, and length?