I liked Vic Fontaine and the baseball episode.
I also liked the Nog/Vic episode. I agree, a little break from the gritty war was majorly welcomed. I'm not a fan of darkness myself. and DS9 was a very dark series.
Just look at the episode where a whole planet of descendants was wiped out due to a time travel goof ;o).
Or the one where they assassinated a Romulan Senator and framed the Dominion, or Jake dealing with cowardice in combat, or the one where a Federation Admiral was leading false flag missions, or the Benny Russel episodes that left us wondering what was real...
In terms of "dark" it definitely went where no Star Trek had gone before.
But they also had some of the most comical stuff as well...The tribbles, or pretty much anytime Quark was on screen, or the baseball card/cell regeneration and entertainment pod.
The stuff that bothered me was when they got too heavy handed with social commentary. The religious commentary wss a big one, but also racism. Previous Treks drew parallels (the left side of his face is white, vs right)... Whereas Sisko was still upset, three centuries later, about how blacks were treated in early 20th century US.
He even refused to visit Vics over it. That would be like modern New York Jews refusing to listen to Spanish music because they are still pissed about the inquisition. I know the comments were still very much relevant to the viewing audience, but it broke the fourth wall a bit by not leaning on allegory the way other Treks have.
I'm not sure I said that very well... Let me try again: you have to have social commentary. It's a defining characteristic of Star Trek. But it should be couched within Sci fi. Otherwise it just feels unnatural for characters to realistically care that much about things that happened four hundred years ago, on the other side of the galaxy, in countries that haven't even existed for centuries.