It seems too much to ask for two stellar episodes back to back this early in the season. While Q-Less is nowhere near the disaster of Babel, its also nowhere as great as Captive Pursuit. Q-Less is kind of middling. I think it's partly because the series had yet to find its legs, and the writers tried to use Q to differentiate the show from TNG, rather than truly explore how it's different.
The episode begins with Bashir framing his Starfleet medical exams in terms of a great battle, while attempting to woo a Bajoran woman. Bashir mentions at this point that he was the salutatorian, and not the valedictorian of his class, having made a mistake awash in techno-babble of post-something, pre-something that sounds the same. As "brilliant" as Bashir assures us he is, and as full of self-assured bravado, this seems an unlikely mistake for him to have made. It's a little seed of a story to be examined further in later episodes.
Sisko's encounter with Q in Quark's is entirely framed within the relationship Q had with Picard; Q acts as the aggressor, presenting Sisko with the opportunity to show the baser instincts of humanity. Where Picard - ever the statesman - would refuse to react, Sisko doesn't hold back, and hits Q back. While this may be effective in characterizing Sisko, it is once again compared to Picard. It really comes across as a cheap tactic, and not nearly as effective as doing something different.
More to the point, aside from this brief encounter with Sisko, Q seems rather disinterested in anyone other than Vash, whom Q had convinced to run away to explore the galaxy in the TNG episode "Qpid". Q is quick to play the martyr, unjustly accused for threatening to tear the station apart, but fails to offer any suggestions or aid in solving the problem. This could be seen as part of his test for humanity. If they can't solve a little problem like this, why should humanity be allowed to spread like a disease across the galaxy?
Yet the crew is eager to blame Q, rather than ask him in humility if he was responsible. I do have the feeling that if he was asked, Q would answer honestly (the nickname "God of Lies" does tend to be misinterpreted).
Q's motivations in this episode are completely out of character. It's difficult to believe that Q would be so enamoured of his companion that he would spend so much effort keeping her around. From what we've seen in TNG, he is far more… inconstant. Q is like a child with new toys. He's always interested in new ones, but quickly loses interest. Aside from his promise to Picard in Qpid to keep Vash safe, there is little to suggest that Q wouldn't just abandon Vash somewhere when he encounters something shiny.
There are some other comparisons to be made with "Encounter at Farpoint", as the source of this anomaly turns out to be a embryonic life form which turns into a space-borne alien. Aside from being the source of the danger threatening the station, it's essentially a MacGuffin.
Vash's subplot involves selling artifacts from the Gamma quadrant through Quark. While there are some amusing interactions here, the Ferengi susceptibility to people massaging their ear lobes seems a rather obvious evolutionary flaw. This practice was first introduced in the TNG episodee "Ménage à Troi". Despite Quark's inability to resist Vash, he shows the Ferengi business sense when running the auction, cutting short the lectures on the items for sale, distilling them to "Friends, it's rare, it's beautiful, and it's a gamma quadrant original, and it can be yours for the right price." While he's not a brilliant orator, he knows his customer base well.
Although Q's motives don't match my expectations, it's easy to forget this, and just watch John de Lancie. He's a brilliant actor, and he's quite good at portraying Q. It's just sad to see his character and his acting wasted on an episode that could have been so much better, had they focused on Q's normal behaviour. I would have loved to see Q's character developed further, or at least seen some real tests of the DS9 crew. But as John de Lancie notes in the Star Trek: Deep Space Nine Companion, "Q is best used when he deals with large philosophical issues. And skirt-chasing just isn't one of them".
Q-Less first aired February 7, 1993. Teleplay by Robert Hewitt Wolfe. Story by Hannah Louise Shearer. Directed by Paul Lynch.