I think the novels have suggested some ideas that might have worked well as a movie. I'm not sure why the Bajorans would have a civil war now, but I guess I'd be open to the possibility if there was a compelling underlying reason.
But again, I can't see a movie that was strictly limited to DS9 elements being especially popular, and as I've already slammed the later TNG movies for not acknowledging the larger Trek universe, I'd be quite the hypocrite if I wasn't willing to say the same for a DS9 movie that did the same.
I don't think that a DS9 movie would carry a wide audience as well. My own suggestion of a Civil War would be something that could follow from the death of the Kai as the Federation's major critique (and erstwhile partner) and the probable reorganization of opposition that would likely occur. It's just a speculative suggestion, giving something to discuss, rather than speak in abstract about how a DS9 movie might work.
I'm not sure the novels give much of an indication of a possible path: they tend to use the characters with less regard to the setting. Even fighting in the Alpha Quadrant or Cardassia, the crew's focus was always toward the station and Bajor.