One of the most balanced (and productive) teams I've worked on was under a general manager who had 8 kids and made it a point to attend _every_ event they had and go on regular vacations. Since everybody ran into his policy at some point (reviews scheduled at 5pm canceled or him out of town for a week or two), the whole org was pretty good about doing the same. And it was very different from other orgs in the company, many of which had the usual long hours + weekends culture.