Maybe even a complete overhaul where you choose to help either the Alliance or the Independents in the Unification war, before Firefly takes place, with armies, uniforms, weapons and all that which we see in the small flashbacks we get from the war. Then you may get to meet Mal and Zoë in the war, but the others of the crew didn't participate in the war or it's unknown if they did (so you may not meet them) and people would most likely choose to fight for the Independents because who would like to kill Mal and Zoë? :s Anyways, a complete overhaul as an alternative story of Firefly would be cool aswell, and probably funnier/easier. It could be that you are travelling with Firefly, you know like Book and Simon before they joined the crew, and then they have to stop/hide/crash on some planet/moon for some reason (the planet/moon where the story would take place) and you could either help them or work against them (duh!), whatever rocks your socks. There would be feds after them, and after Simon and River. There would be reavers that'd like to eat you. There would be Alliance-friendlies who very much would like to beat you down in a bar brawl. But best of all... THE CUNNING HAT! No, just kidding. ;) Best of all would be that the story would be able to continue past where the series ended, fill the gap between the series and the movie you know :) Because I would very much like to know what's up with Book, what's his connections with Alliance and is he really a priest? There's also Simon and Kaylee's feelings (although that evolves more later in the movie), Wash's jealousy of Mal and Zoë (which is sorted out in the series), Jayne messing with Simon, Inaras love/hate feelings for Mal and of course Rivers "problems". You know that fed from the first episode? He was planned to come back later in the series because he survived the gunshot, so this could also be his chance.