I bailed on Voyager the first time around because it became too repetitive and I was sick of Janeway's constant preaching. I recently watched the entire stretch (all 5 series from start to finish) and so filled in the holes in all of them that I had missed along the way. Voyager actually got better after I originally stopped watching but I still put it WAY at the bottom because they went off the rails with Q and time travel. Honestly you include it in a series that wasn't cancelled out of the blue but how can we really say that when the series stopped the way it did. That felt way forced. Someone said it had to end that year.
Between DS9 and STNG I'm a toss up. Had I voted for a Trek (I didn't) I would have voted DS9 because I consider STNG to be an 80's series.. else over all I like aspects of both STNG and DS9 better than the other so hard for me to say which wins overall.