In the end, we're left wondering why O'Brien wasn't "mustanged" into a commission when the station's importance and the number of Starfleet officers aboard started ballooning - or replaced outright by somebody with greater command credentials (say, let's import Lieutenant Sonya Gomez to the show!). This is more difficult to justify than the decision not to replace Sisko with a flag officer, as O'Brien isn't a local religious figure (he's just a Storyteller, and something of a charlatan at that).
Agree with this, the command crew on DS9 was pretty thin, once the war broke out you would have thought there would at least be a starfleet commander assigned there to suppliment Sisko, as it was there was only Captain Sisko, Lt Cmdr Dax and Worf and Lt Bashir.
And of those, only Worf was command. It's "nice" that starfleet still let the bajorans hang about but in reality they should have wanted to seriously bolster the staffing on that station, as strategic as it was.
Instead they just pretty much stayed with the same people who ran it when it was some backwater dump.