[Helios78]

I’m leaning towards Deep Space Nine, although TNG is a very close second. What does everyone else think?

[runescaper]

Different factors for different series.

Character development? Voyager; every season seems to show some really good character development for someone.
General entertainment? TNG; They set it up well enough that you don't have to be a "fan" to just jump in and enjoy any particular episode (aside from the second half of two-parters).
Lore? DS9, it gets you deeper into the interstellar political lore than others.

[crzybldthrwr]

Im not giant into the Star Trek fandom by any means, but I definitely dig Voyager.
I just semi-recently started watching and have definitely burned through most of the series pretty quickly :'D

[Gpunter]

DS9 was my favorite followed by TNG.

I'm in agreement with the OP.

[123456a]

For me, the next generation.