Sisko had good material to work with. Also Geordi, Guinan, Tuvok, and any other non-black character who was black on the show. Geordi went from being a junior lt. who didn't trust his own capacity enough to become chief of engineering, and while he was good at his job, he lacked confidence with women. To me, that's a good characterization. It helps that Geordi also looked and acted like an Starfleet officer. Do any of these Academy kids could run and roll to escape engineering as Geordi did several times? Even Picard, the oldest of the crew, could fight.
What they did with the fat black hologram chic was terrible. I still don't know what she's meant to be. You could program her with all emotions, even understanding them because that's in her programming, she ain't like Data in that way. What is the worst about her character is that you could see the difference on how Data acted compared to her: he was someone who KNEW what emotions were, but didn't experienced them so he couldn't act them properly. There was some sort of awkwardness about him and his interactions with others. Sam acts like a retarded zoomer. I dunno what she's supposed to "learn".