Can they be privateers? I think Mal would be a great privateer, although I guess the period is wrong for tight pants. Or, no -- they're traveling actors, always on the verge of ruin (and often on the run from the law), and River and Simon have run away and hidden with them. Mal, obviously, is the head of the company and the leading man. Wash is the playwright, and along with Jayne and Book, plays the supporting male roles. I will ignore the fact that women did not act on stage in this period and make Inara the ingenue and give Zoe the older female parts. Kaylee handles the stage machinery, and would like to act, but forgets her lines. They tried putting River in a production once, and only once, but Simon does quite well, when he can get over his sense that acting is beneath his station. I suspect you could get quite a good comedy story over the time they tried to give River a part.