Fighting is intense but too hectic to be truly sensual. Effort is difficult, thus, a nuisance. A real struggle is really tiring. The "silencing the sentry" is an action theme that captures the intensity of violence at a casual pace. Should the intruder (or escapee) stalk and subdue guards easily then the thrill shall be that of dominance and submission.
Violence can be sexy, especially as art or fiction. Grim, yes, but true nonetheless. Death is fascinating but only to those accustomed to life being valued. It is the virile intensity of sex, violence and slaying that make them so potent and interesting. As artistic themes, there are none more thrilling.
I prefer the "silencing the sentry" scenario to be swift, simple and sexy. Being a dominant heterosexual male I want the victim to be a comely female. Ideally, she is snatched unawares. She may struggle, feebly, but soon goes limp. She may wince from the sting of death but she shall not linger. No blood. No bruises. Her head may dangle from a broken neck and her tongue may be poking out but otherwise her lifeless body is left sprawled and pristine.
I generally do not find unarmed combat interesting. Guns, knives and swords are more stylish and their use more dramatic than that of fists and kicking feet. That said, I prefer unarmed silencing of comely sentries. Direct, physical contact makes the scene "intimate" even if only for the passing moment. The connotation of hands grabbing the body of another with aggressive intent should be obvious.
I am not particularly fond of the "stealing the uniform" theme in its usual context: The idea of one "besting" another by assuming the guise of a friend does not denote warrior prowess. Should a heroine simply need suitable attire, however, I find the stealing of a girl's uniform very sexy. Clothes are personal. Stripping a girl against her will is dominating. Wearing her clothes consummates the domination.
Killing is a must! Tame is too soft to hold an edge. Slapstick is action as a joke. The "silencing the sentry" scenario is impotent unless a matter of life and death.
Sex, violence and death: the three most intense themes of all art and fiction. Like the sides of a triangle, they are strongest when joined together. The "silencing the sentry" theme is a mainstay of action-adventure. As "violence" it is what it is. As "sex, violence and death" it is at its strongest. Done artfully, it is gritty, sensual and simply amazing.