I was just re-watching "reunion" the other day, and was just amazed at what range Suzy Plakson gave K'Ehleyr
during the course of an episode. And how the character is -- she would have been so useful to Picard, in addition to being a logical person to have a relationship with (as opposed to Troi??)
have replaced Troi as the Counselor (or a modified role as Captain's advisor)?
Sure, she was an ambassador, but as we have seen, that hasn't stopped other Trek characters from taking a place on the Bridge.
If not in this episode (which had K'Ehleyr's
dramatic death, that certainly works for the story)
...then maybe an alternate K'Ehleyr
somehow following Worf to the Enterprise.