Overachieving females seems to be the common thread in most of the Heinlein Novels. This is not to say that the men are incompetent, although as noted earlier the men in The Star Beast are almost cartoons in their conventional male pattern conservative bumbling, but the competence of the men is as a foil against which the women show their capabilities and intelligence. A common theme is a male character assuming incapability in a female only to have the capability shoved down his throat in the next paragraph.
Zeb said, "Huh? Sharpie, there's no time for that; there's something dangerous around! You girls get inside before I--"...
"Chief Pilot, there are no 'girls' here; there are four adult humans." The Number of the Beast, 1980. (NOB) 219.
She goes on with a chain of command explanation, she being on top by being the most competent for command by consensus.
The first two thirds of NOB is an exercise in sorting out competence without regard to gender assumptions, and not incidentally how this sorts out in the context of conventional marital expectations. Both wives get pregnant early in the story which adds the spice of continuation of the species of super competent humans to the mix. It is also an extended lesson on how even pregnant competent females can believably achieve their designated roles in an adventure story.
1980 was early in the recognition of female competence, particularly mothers. A the time a male department head in a University was unable to introduce a professor mom on his staff as his native language had no word for female colleague. NOB was a very early exercise in exploring the implications of a pregnant woman in command of a mixed crew in a series of life threatening situations. As usual Heinlein has worked out a coherent philosophy for women taking a productive and reproductive roles in a pioneering adventure story.