Since the outdoor man cave is more likely to be used by the entire family than the indoor man cave, the outdoor version might need to be toned down a bit. In order to keep it man-centric without alienating the rest of the family, consider centering the action around a well-built outdoor kitchen versus a horseshoe bar. You could even build an outdoor bar to go alongside the grilling station as long as you don't go overboard with the sports bar theme. Add an outdoor pizza oven for authentic, wood-fired pies that are sure to be a summertime delight for the entire family.
The best way to make sure your backyard man cave functions for the whole family is to include them when it comes time to design it. Make sure that your kids have their own space by incorporating age-appropriate games and activities they can enjoy as well. And it's never a bad idea to get your wife in on the action. Not only will she likely lend some aesthetic appeal to the project, she'll surely appreciate having a role in creating her man's cave.