Well done
Don't mind the whiners. No matter what you do, you can't please everyone ... but this is going to please most of them ;)
As to your question, I'd say do both a game (series) and movie, ala Resident Evil, et al. What's always seems to work best is going back and forth between the two. This trailer sets the backstory for the game. The game then finishes with some unanswered question, which sets the stage for the next movie(s), which are used to establish the storyline for the second game, and so on. As a bonus, it allows you to go back and forth between working on a game and a movie, giving some variety in the actual work while remaining focused on the same plotline.
Even this backstory still has some background gaps that still need to get filled in ... like why Muzukashii went from whining about the time to an "I'll be right there" upon hearing about Ray's disappearance, what is Melon Corp and why do they have their own :on call" assault team, who trained the Sweepers (save the master is always good for a game basis), when did Kirby become a PDA, and so on. Plenty of loose ends upon which you can base later projects =)
Graphically, I've got one issue with the flash. The variety of different 3D styles you are using is visually jarring. Granted, as a trailer, it's not actually supposed to have an overall flow to it, but switching during the upcoming game(s) or movie(s) is going to mentally break people out of whatever scene you are staging.
I'm looking forward to how this turns out. Good luck!
