Mackers is basically dealing with a living nightmare throughout the play. Unlike the Dane, he doesn't dance around the issue of suicide and dismisses it as cowardice. It helps that he assumes that he is invulnerable - which certainly lets me get away with such flippant choreography.
Macduff's focus on revenge is also keenly displayed this way - attacking someone with their back turned is not gentlemanly. He did invite Mackers to turn and face him, to his credit, but there's obvious anger and issues at work here.
Extra fun tomorrow!
Looking good so far! I guess the King's arrogance is his own demise, here? :D