I'm sort of nervous about other Star Trek series, since what I love above all about DS9 are the complex, years-long, serialized plot lines and character arcs, and I'd heard that the other series are in a more episodic, standalone format. On the other hand, my only exposure to non-DS9 Trek are a couple of TNGs, which might have been the TNG equivalent of that DS9 where Worf joins a fundamentalist sect on Risa or whatever, Jandrew Edits, the new movie, and an episode of Voyager I saw as a small child (I think it's the one where Earth manages to contact them or something), so my opinions are mostly second-hand and perhaps unfair.