I like Jaina, but her and Sylvanas have become eerily similar over time.
My primary distaste for Sylvanas is the utter disregard for the nuance of her story, and they keep incorporating her into a wild new plot line each expansion that has no proper explanation or context. We've been dealing with her crap writing forever, and she was basically MIA for all of Legion doing next to nothing after a bunch of disjointed setup.
Comparatively, they actually wrote in most of Jaina's anger and explained each cycle of hatred she went through. Sylvanas? Nah, they just change her motives and reasoning, and try to sweep it under the rug of "she was really doing it for this reason all along!" Both characters have a similar writing style, but the execution for Jaina is just... better. Specifically to BfA's storyline, it's all butts, but I feel like Jaina came out better.
I like that Anduin's compassion gets a lot of doubt, though his interactions with Sylvanas are pretty questionable. (The latest custcene was like: I understand you better than anyone. All of a sudden. Without knowing your motivations. /s)