DS9 was an ok show, but I never could get into it. And I actually disliked the Soap Opera feel that it had a lot of the time. I think it's because it was about a space station and they weren't really discovering much. (Until they got the cloaking ship at least.)
I have to say that my favorite of the different Star Trek Series was Voyager. TNG was cheesy the first couple seasons, but it got to be good, but it started having that DS9 Drama feel to it at the end.
When they did Voyager, they got back into the Space Adventure aspect of the show's past and it was fun to watch.
Enterprise was an "ok" show, but they effectively destroyed Star Trek's Cannon with no regard to the fan reaction. I think if they had at least TRIED to follow cannon, that show would have had a long life.