Why did God create man first? Because She wanted to start with something simple.
Just because something sounds funny, doesn't mean it is not true. But the concepts of masculinity and femininity are not just related to men and women. Rather men and women are particular instances of these concepts. This latter statement has many important implications, the most important of which is that men and women and their sex-based characteristics are not mere artifacts of biology, evolution, or need for procreation.
Masculinity and femininity are defined in terms of characteristics that are found in live creatures as well as inanimate objects. These concepts are defined in terms of modes of actions or reactions or how they manifest themselves. In particular, whether such actions or reactions are concentrated or distributed. The masculine characteristic is related to concentration or focus, while the feminine characteristic is related to diffusion or distribution. Concentration and diffusion are basic and complementary traits of any system or process.
Baha'u'llah and Abdu'l-Baha, expound, in several tablets on the station of women and their place in human affairs, and that men and women are "co-equal" and "complement" each other. Abdu'l-Baha also explains that men are distinct from women because of the forceful nature of both their bodies and minds. The "forceful nature" is closely related to the masculine characteristics as defined in this paper.
These characteristics are applied to men and women at various levels of detail including sub-cellular, cellular, physiological, anatomical, emotional, cognitive, and behavioral. At each level, the masculine and feminine traits manifest themselves in a complementary fashion, sometimes distinctly and sometimes more subtly. These differences are purposeful, not arbitrary. As it turns out, the masculine characteristics also tend to make men simpler or more straightforward in terms of their behaviors and interactions, as indicated by the opening remark above.
It follows that men and women are complementary at fundamental levels and as such, both are capable to perform any function but in different manners and with different emphasis. Such complementation does not confer privilege or priority on either sex. It provides the specializations necessary for collaboration and achievement. It further follows that although men and women are not the same in characteristics, but they are equal in the rights to exercise their characteristics freely.