No, it definitely wasn't Keiko. Maybe there isn't another character and it just feels like I'm missing someone even though I'm not. The only other non-Q (and Vash) characters that I can think of are all Klingon and DS9 didn't change my opinion on Gowron, Lursa and B'etor, or Kurn. I take that back, it did make me like Gowron less.