Is your protagonist male or female?
I wonder if most of the main characters in novels are the same sex as the author.
There are examples of famous writers have failed when they have based their novel on the opposite sex.
There are also famous authors who have intelligently avoided the pitfall of writing about the opposite sex.
‘The Professor’ by Charlotte Bronte is based upon her experiences in Brussels, where she was a teacher in 1842. Much of the same subject matter of 'The Professor' was reworked from the perspective of a female student into Brontë's later novel Villette, which attracted MUCH HIGHER critical acclaim.
Jane Austen wrote about men in situations she was most familiar with. In her personal encounters with men. In situations when both men and women were present. But she knew little of what men spoke about in the absence of women.
Austen avoided pitfalls by writing about what she knew.
Jonathan just won the internet
I know a female author who writes realistic men as main characters, but I wouldn't fancy trying to write a woman.
I have enough trouble understanding how real ones work ;)
My main character is female, this I think, will make the story better as I can understand the way females think, better than I would male characters would think. However I always have a strong male character too, although he has a smaller less in depth part.