Nicole Janeway (Geneviève Bujold)
Yes, it seems a bit off doesn't it?
Bujold just doesn't have same warmness as Kate Mulgrew. VOY had some good performances and Mulgrew does a great job because she has a softer tone to her performance, but still keeping it strong. Bujold doesn't seem to have a strong presence either. When Bujold was playing the role the character was called Nicole Janeway. (She wanted the name Nicole) You can notice that Bujold keeps her distance from everyone while Kate seems to always have a closeness to people.
They were filming the pilot when Bujold promptly quit show after a couple of days of shooting. From Memory Alpha, ((She quit after a day and a half of shooting, with the public reason being she was unaccustomed to the hectic pace of television filming. Other rumored reasons included dissatisfaction with her performance on the part of the producers and dissatisfaction with the character on the part of Bujold ))
Rumor has it, she had a breakdown on set with the entire crew and actors watching. The director got angry with this display of weakness. He said, "Don't act this way, you're the captain."
From Memory Alpha, ((Berman also recalled that after working on the set during the second day of shooting, Bujold went to her trailer in tears. Later, both "Caretaker" director Winrich Kolbe and Berman met with her there and asked her to go home ))