Armor is armor, its primary purpose is to provide protection in battle. You could argue that armor could also be visually designed to look intimidating when considering the psychological aspect of warfare, but even that has nothing to do with looking masculine or feminine. This is in terms of reality, though. In fiction, you can do pretty much whatever you want, and bend the rules to make it work. That being said, it doesn't really matter what stormtrooper gear looks like. It blocks blaster damage about as well as a paper blocks a bulldozer, at least in the movies.