In terms of superiority TNG was more effective than DS9. Looking back a pop culture and you'll see which shows had the most impact. TNG was so popular that it transcended from the circles from science fiction fans to that of regular pop culture, much like TOS people now days know who Picard is as much as Kirk, can you say the same for Captain Sisko? Thought not. Now I'm not bashing DS9 here but what I am saying is that while DS9 was a good show in that in brought something new yet familiar to the Trek series it didn't break free of the bounds of being within the niche that is Star Trek fan base. Sisko was a different Captain to that of Picard and that was his thing, Picard's mission was that of peaceful exploration, while Sisko's was that of enforcing the peace while on the frontier/borders surrounded by enemies, so really comparing the two, for me at least is just plain stupid when neither would function in either environment. So when judging a show on which is superior, there are many ways you can look at it, hidden gems/diamonds (like Babylon 5) to those which have the greater impact our media culture. TNG did that. DS9 did not.
When I watched DS9, it is one of those shows where I felt the supporting or recurring characters are more effective than the main ones, personal opinion I know. But I found Garak, Odo and Quark to be far more interesting characters than the Starfleet personnel.
Until the Dominion Conflict came .Sadly while this conflict was also its high point to true trek fans if you want to call them that, it was also a bad move. TNG teased the fans of seeing these incredibly powerful war machines, the galaxy class starship and Romulan Warbird almost come to blows but yet it never did, however in DS9 this once powerful engines of destruction were portrayed as something made out of a crate paper and were disabled/destroyed after 3 phaser shots. I know it was the FX budget that restricted it however they didn't have to have thousands of ships on screen, sometimes less is more you know?
Voyager to me, was just horrible, absolutely awful. It did have some good episodes here and there but those were few and far between. It was to me the SGU of the Trek world, then Enterprise came around. Oh fuckeroo! The same applies to the Trek Movies (the TNG ones that is), those were just dumb action movies that are not related to the characters of the TV show but in fact the opposite to how they would and should react to given situations, it effectively broke its own universe. Generations, First Contact, Insurrection and Nemesis were just awful.
I know its just my opinion but I do like DS9 as its own independent trek show
Anyways, wuv you's rac80!