Every boy/man comedy cliché you can think of is folded into this sitcom, but the "all-male" concept is its primary selling point. Like every "big family" show ever made, each child is a high-concept "type" rather than a person (though of course this can change if a show has enough time to mature). In the interest of comprehensiveness, however, Complete Savages probably has at least 3 or maybe 4 too many characters. Keith Carradine isn't the same-old sitcom dad and brings a freshness to an old formula. The Uncle Jimmy character could fall in a well and not noticeably change the show.
As for the boys, they're all different (too different to all come from the same family, but that's probably a little too meta for a modern sitcom to worry about) and each has potential in his own way, but I think there's simply too many to develop in a half-hour show. I think I would have dropped the two youngest and concentrated on the high-school crowd. Chris is too stupid and Sam is too nerdy, but Jack is a fairly well-drawn character. Given time, they'll all smooth out. Most important is that the situation be allowed to evolve if the show is to last longer than a season or two.
As for the boys, they're all different (too different to all come from the same family, but that's probably a little too meta for a modern sitcom to worry about) and each has potential in his own way, but I think there's simply too many to develop in a half-hour show. I think I would have dropped the two youngest and concentrated on the high-school crowd. Chris is too stupid and Sam is too nerdy, but Jack is a fairly well-drawn character. Given time, they'll all smooth out. Most important is that the situation be allowed to evolve if the show is to last longer than a season or two.