Pros
The people at Greenleaf are generally smart and great to work with. Management is getting better at hiring, and also at weeding out those who don't fit. Each new project is something different and interesting, and yes authors can have strong egos, but employees who are flexible and opportunistic can grow with the company. There's a lot of emphasis on work/life balance, quarterly outings for fun and to serve the community, and then little perks like free sodas, breakfast tacos at meetings, etc.
Cons
If you're looking to climb a corporate ladder or just collect a paycheck, this is probably not the place for you. It is a smaller company without a lot of hierarchy, which is great as far as getting stuff done but there aren't a lot of ranks to climb up. Authors can be demanding and certain roles show turnover from that.