Yeah, it was cancelled too soon. With a lot of shows--Arrested Development and such--it feels like the cancellation was a blessing, helping them bow out while they were still on top. With Firefly it was clear Whedon had a long-form plan, which is something he does very, very well (and which so many other genre shows don't). Having it end abruptly in mid-first-season is a crying shame, and while it's nice that the movie provides closure, there was clearly a LOT more they wanted to say. Among other things, Whedon obviously wanted to explore the pros and cons of libertarianism, statism, anarchy, totalitarianism, and all the various nuances in between. I believe he's said that he doesn't agree with Mal, politically, and that he wanted to explore that in more depth. But the truncated space means that the conflict was largely reduced to the EEEEEEVIL Alliance vs. the heroic punk-rock space cowboys of freedom, which is fun but not very substantial. Ironically, the only episode that tackles these themes in a challenging way, that makes a case for the Alliance being something beyond simple villains, is The Train Job, which is arguably the worst episode of the series. So yeah--even a full season would have helped to scratch the itch.
Also, I'm still dying to know what was up with the Blue Hand Group and Book's backstory (yeah, I know there's a comic, I've heard it's pretty bleah and I don't want to taint the show by reading it).
