Do bisexual men, I mean men who may at one time have been married and had children, tend to be less stereotypical and more masculine than men who are strictly gay and have never been with women?
First, just because a man has been married [to a woman] had sex with women, or fathered children in the biological way doesn't necessarily make him genuinely bisexual -- but that's for another post.
Most, but certainly not all, gay men do a little experimenting in their younger days, some fooling around with the opposite sex, until they get it on with a guy and realize they've found what they're really looking for, and most have little interest in pursuing heterosexual relationships after that or toying with women's affections. Whether a man is stereotypically gay or not has absolutely nothing to do with the amount of experience he's had with women. I've met very masculine guys who've never had sex with a female, and very effeminate men who not only sleep with both men and women [without necessarily being bisexual] but have gotten married and fathered children. I'll never forget a party I went to one summer when there was a guy swishing around the room proudly showing off his wife and their new baby. If there are macho gay guys there are also effeminate straight guys, but somehow I didn't get the impression this fellow was especially straight.
I discovered over many years that the more you try to pigeonhole and stereotype the members of the gay and related communities, the more your expectations -- if your eyes are really open -- will be confounded.