I kinda liked each series of star trek. I thought voyager was halfway decent, could not get into Babylon 5, or the new Battlestar. As for space/sci-fi, my favorite of all was Farscape, excellent writing, superb character development. Just my opinion.
Mine, too. John Crichton went from an wide-eyed, enthusiastic, compassionate innocent to a cynical, shoot-first kind of guy, while the selfish, suspicious, me-first aliens all became more compassionate and learned to work together. (Yes, even Rygel.) It was a fascinating series.