1. DS9
Great storytelling, characters development, and had the greatest story arcs and the Dominion War
2. TOS
A very very close second, the one that started it all, and because TOS makes me nostalgic, the Kirk-Spock-McCoy trio was very nice
3. TNG
Went on TOS and expanded with great episodes and diplomacy, but I liked TOS better because it was more fun
4. Voyager
Great episodic format, but a bit too inconsistent and could never be like TNG, but it was still very good
5. Enterprise
Was just getting good when it got cancelled, might have ranked higher if it continued
6. TAS
Great continuation of TOS, with some pretty good episodes
7. DSC
Too early to tell if it's good, but so far, pretty good