Extreme Measures (*½)
Since whittling down the various arcs to just two stories worked out so well for the previous episode, going even further and just focusing on one story should be awesome, right?
No. Extreme Measures
is a mess. There are a lot of reasons for this. According to Memory Alpha, the original plan for this arc was that Kira and Odo would head to Section 31's headquarters to discover the cure, but then the decision was made to send those two characters to help Damar's rebellion and the idea was adapted for Bashir and O'Brien. Then the budget for the episode was cut considerably and the story had to be adapted to take place entirely on existing sets, so Section 31 had to come to DS9. In the desire to do one final O'Brien/Bashir adventure, and with the need to pad the episode out for an hour, the writers came up with the idea of the story taking place inside Sloan's brain.
In my opinion, the core problem was the desire to turn this plot into an O'Brien/Bashir adventure. Section 31 is a conflict of ideologies, it's at its most interesting when it's just two characters in a room arguing with one another so that us wannabe intellectuals can fawn over the show's brilliant moral complexities. It's not the right venue to attempt a buddy comedy. This is an organisation that has attempted to commit genocide and murder a member of DS9's crew, so as amusing as it is to watch O'Brien awkwardly refuse to admit his platonic love for Bashir, it's out of step with the gravity of the situation they're in.
Making things even more disappointing, the first 15 minutes of the episode are really strong. There's a touching scene between Kira and Odo, there's a neat scene where O'Brien and Bashir have to explain their plan to Sisko, and there's several good scenes between Bashir and Sloan. Things only go downhill once Bashir gets the bright idea to go into Sloan's head to find the cure, at that point it becomes a generic sci-fi mind-screw adventure.
It could have been so different. All they needed to do is take that first 15 minutes and pad it out a little bit with a few more scenes between Sloan and Bashir, then fill out the rest of the episode by pushing ahead with the rest of the final chapter arcs. Show Kira and Garak returning to the Cardassian rebels and set up the following episode's mission to Cardassia. Show some scenes of Martok adjusting to his new role as Chancellor. Maybe add a scene or two of Rom and Nog working to decipher the Breen weapon before Rom becomes Nagus in the next episode. There could be a scene between Sisko and Ross about Sloan and Section 31, and the dirty deals those two characters have done in the past. At this point, DS9 is an exciting playground of stories and characters, so the decision to focus this entire episode on just one of those stories and two of those characters was bizarre. Maybe the version of the episode I outlined would have been two expensive because of all the actors involved, but it would have fit a lot better in the final chapter than the episode we got.