I think maybe you should go back and rewatch the episode, and perhaps the series. In that episode and several times throughout DS9 Odo totally called out Starfleet Security for being inefficient and ineffective and not just in regard to DS9. Worf spent the episode trying to prove Odo was bad at his job, and in the end Worf found out he was the one that was overstepping, not understanding the job and kept getting in the way.
Odo also doubled as security officer sometimes on the Defiant, so yes he did a good job there too from what I remember.
I'm sorry there is no way you will convince me Reed was ever a good security chief. The two examples are enough evidence for me, but I specifically remember me and my friend laughing a lot at his ridiculousness.
The others there can be a debate on. Sometimes they were good, but there are still some really incompetent things they did IMO. And again, it's mostly going to be story reasons to move the plot along.
You did bring up a point that was always something that did irk me with the chief of security/tactical officer. Those are two totally different jobs with different skill sets. To me it explains why Odo was a good security officer where I don't think the others were because they were more tactical officers meant to work a bridge station, and not security on a ship.