Pros
As others have said, the building is gorgeous. You get to feel good at first because you feel like you're helping underserved communities. If you actually get the go ahead to work on a worthwhile project, you can get some quality work done.
Cons
Zero professionalism from management and CEO. For a nonprofit that talks about diversity and inclusiveness, you would expect a a more open-minded and, frankly, modern attitude around the office. Any suggestions for improvement are shot down by threatened members of upper management and there are no opportunities for anonymous feedback. If you are made to feel uncomfortable by a coworker or worse, the CEO, there's no way to report it without fear of it spreading through the office gossip mill and coming back to bite you.