I think there's some confusion here between Ranks and Positions..
They're separate because the Positions are going to be either on a voting rotation or by appointment, and not a reflection of attaining rank. This means that if someone is in-charge of a unit, but get's voted-out, they fall back and become part of that unit as a regular member.
It's not a punishment, by any means, it just allows pro-active and popular members to move into Positions where they can do the most good for the club. The previous position holders are still eligible to get back into that position, or other ones, at a later date, or take a breather and continue on where they're most comfortable. Members have very little to do, in terms of duties outside of events, but Position holders can be very busy people, attempting to maintain the club, and/or get it into postion for future events, every one is a volunteer.
As far as member ranks go.. we might have SOMETHING, but I can't see it being used for anything other than for order during drills at events (which I really hope we do), or role-play stuff. It could be based on participation and merely reflect how active you've been in the club, but as far as "Hey private! go get my slippers!" it ain't happening. We aren't a military group, we're just a costume club that is ordered in a similar fashion to be as effective as possible at doing what the group, as a whole, wants the group to do.. Organization of volunteers.
The Position folks will need to be followed if the club is to function though. That shouldn't be TOO hard to figure out, and again, those orders are in terms of trying to keep order.. ("Hey, quit punching that guy! we're trying to look official here"), not to maintain command pressure ("You eyeballing me son?!","Stand at attention and guard that bucket until I releive you.. there better not be ANY water missing when I return!") unless it's part of a skit or something that you volunteered to participate in.
It shouldn't be too hard to follow the postion folks though.. Kinda' like listening to the Mods in the forum, except even easier because most of them will have been folks that your unit has voted to put in there, or appointed by someone your unit voted for. Heck, there's even a system being designed that ensures position folks don't abuse their postions.
Other than that, there's just following basic rules, being respectful of others, and participating, as long as you're doing that, noone's going to tell you to do anything.