Pros
Excellent benefits package, very strong pay for professional roles at least and relative to other top universities in the higher ed sector, people / staff who are very supportive and focused on the mission of serving students, (sometimes difficult) faculty, and researchers. Great place if you are junior or mid-career and looking for stability - i.e., at a single "place" because it is so large, that if you are a strong performer you can move to many different departments, centers, labs, etc. and find neat roles there.
Cons
All that said, Harvard is definitively NOT the best-run organization in the world though it may be one of the world's leading academic institutions. High, high, high politically-charged environment - need to be able to work effectively with many different sets of stakeholders, including faculty (who are often treated as 'free agents' in academia). The higher up you are, the less grace. Harvard has armies of people to keep itself out of the news and that impacts culture greatly. Overall, at the center / central administration, and leadership levels, fear of screwing up rules the day because the implications are very far-reaching (they are Harvard). So lots of risk aversion deep in the DNA of Harvard. Also just keep in mind that this is academia -- as one dean told me when I was there -- "universities are for people who society cannot otherwise employ" and the old adage of "those who cannot do, teach"... You just have to be able to pull off whatever it is you're charged with achieving in a way that brings in faculty... cannot upset faculty...