The thing about Ivanova was that it literally took her four years to grow on me. Claudia Christian was painful to watch in most of season one, and she really didn't begin to seem comfortable in the role until season two. It's really not until her scenes in "Rising Star" (and, later, "Sleeping in Light") that she worked for me as a character (her painful left hand of vengeance monologue a few episodes previous didn't help bring me around)--and those were her last two episodes!
Lochley, on the other hand, is a mixed bag. She's intentionally left out of most of the first quarter of season five, and it hurts her development. Her scenes with Garibaldi seem forced throughout, and she doesn't have any chemistry with Boxleitner (and maybe that's the point, but they still aren't very good in their scenes together). On the other hand, once Gary Cole is introduced over on Crusade, the character (and the actress) suddenly come alive for me. I wish we could have had more episodes of that spin-off, if only to further Lochley's development.