I think it's great that they are not making BoJack "just the douche" character. Backstories help a lot but it's also just about setting up the scene: can people be good in the environment? What are the motivations, challenges, triggers, and obstacles? Who defines happiness?
"One thing that I've learned about love, is that it is a lot like moving to a new country, trying to build something where nothing existed before. It's hanging on and letting go. It's messy, it's beautiful, like any giant leap of faith."