Maybe you're going about it all wrong then and you need to go back to the basics. What do they wear, what do they need? Draw that, and then maybe add cool stuff. This guy doesn't look like a mall cop, he doesn't even look like a swordsman.
This is what a security guard looks like:
Here's a diagram that breaks it down....
I think you need to start with observing the subject matter in video, picture, etc before you can really feel inspired to make it.