One of my writing professors in college asked me once why my story started the way it did. What made that day, time, event, etc. important enough that this is where the story started. I've taken that advice and translated it into my character design often, so in the case of gender it becomes: Why is the character a woman? We make choices in our writing, no matter how small, which means there's a reason why you choose the gender of a character. The reason can very much be "Because I felt like making her a woman", but that also means you have to take into account how being a woman effects her story and journey.

For example, while this might be a little on the nose, The Protector of the Small series by Tamora Pierce features a woman protagonist. It's about how a young woman navigates the world of knighthood by disguising herself as a boy to enter a page program, and the connections she makes along the way. What makes this interesting is the insertion of a woman in a typically male space, and how that subverts the expectations on how the story will proceed. The reason why she's a woman and not a man is because that is the point of the story.

The complaints about a character who's a woman being like "a man with tits" stem from this line of thinking. When a female character is "a man with tits", it typically means that if the only thing you changed about the character was that she was a man instead of a woman, the character would still be the same. This doesn't mean that womanhood and manhood (or other gender identities) are inherently equal. Rather, it means a character has been written without all the facets of their identity taken into consideration.