Bashir
Kira
Garak
Benjamin Sisko
Quark
Dax
Odo
Worf
The O'Briens--
Pretty much everyone with zero exceptions. They nailed it from day one and what blossomed as a result was magnificent. All distinct personalities yet fitting into the 24th century mold without looking like the two extremes of:
a) contemporary people from the late-20th century, which is lazy character scripting
or
b) the sort of robots that TNG got lampooned with. You remember the good old days of "Data was the most human character on the show and he uses contractions when he's not supposed to and has emotions when he's not and yadda yadda yadda", which - despite getting kudos for being sci-fi is still an extreme. TNG was miraculous that the characters were watchable despite nearly all being all proto-Vulcans and/or popsicle stick nonpersonalities. Which is rendered sadder by the fact many of them had personalities, which were curtailed or cast members left. DS9 fixed those TNG issues and nailed it.
Characters being different in personality, even arguing or being taken aback, yet they all get along when needed. A great example is from the get-go when Bashir and Kira meet. That's a damn good scene. Ditto for Siskocompelling Quark to stay in a neat parallel subplot to his own being convinced to stay on DS9. "Emissary" has a few nitpicks but everything else is so strong, the nitpickies are rendered moot.
Showing Sisko from the get-go as not being a Picard clone, and with aplomb.
The Dominion became a credible "big bad" and never got watered down l;ke the Borg.
The Defiant.
Seasons 2 and 3 were already largely refined (and season 1 wasn't and had a couple real belters in the mix, like "Duet") bad but season 4 was the shot in the arm the franchise needed. It's a reboot that isn't a reboot. If that makes sense.
TNG was always dessert. DS9 is the entire meal, with napkins and silverware, and allowing a little burp o' appreciation when done.
