May be wrong on this but as far As I understand the concept of the rp, its like each of character(or 2 at once) will get a introduction mini arc? Like in one piece.

So after angelo joins the captain its a question whose turn will be next to join the crew. Everyone else who isnt joining or already joined makes stand in characters/temporary characters of bad guys the main character(the pirates of Abbys crew) can beat up and fight against.

Its a nice idea of having mini arcs for each character, pretty good for character development, the only downside is the wait. 

*shrugs* and nope, not having any idea whose is joining next XP 
But I am Sure one can make as many marines one want right now to make the jail break a problem from weaklings to stronger ones.