Every Main Character should have a gender. Whether your Main Character is a horse, a house, a person, or an alien, the audience will not be able to empathize with it unless that character’s mind functions in a male or female manner.
If you want your Main Character to tend to look for linear solutions to his problems, choose Female Mental Sex. If you want your Main Character to tend to look for holistic solutions to his problems, choose Female Mental Sex.
NOTE: A character's Mental Sex need not match its physical gender.
Much of what we are as individuals is learned behavior. Yet, the basic operating system of the mind is cast biologically before birth as being more sensitive to space or time. We all have a sense of how things are arranged (space) and how things are going (time), but which one filters our thinking determines our Mental Sex as relying more on patterns or Intuition respectively.
Male Mental Sex describes spatial thinkers who tend to use linear problem solving as their inherent method. They set a specific Goal, determine the steps necessary to achieve that Goal, then embark on the effort to accomplish those steps.
Female Mental Sex describes temporal thinkers who tend to use holistic Problem solving as their inherent method. They get a sense of the way they want things to be, determine how things need to be balanced to bring about those changes, then make adjustments to create that balance.
To be sure, we can go a long way toward counter-balancing those sensitivities, even adopting the other approach by circumstance and/or choice, yet underneath all our experience and training, the tendency to see things more in terms of space or time still remains. In dealing with the psychology of Main Characters, it is essential to understand the foundation upon which their experience rests, for the very mechanism of your story’s structure depends upon it.