I had no idea that Zelena's pregnancy was planned that long ago. It felt to me like it was an impulsive, poor choice but knowing that it was planned for that long just makes it worse somehow. They had so much time to change their minds about it and didn't. I just don't get it.
I think with Cora, Regina had the much better, stronger storyline. Even in "Sisters" when they were all 3 in the Underworld, I felt like Cora was more focused on Regina than she was on Zelena. The difference I see is that Regina doesn't often talk about how Cora hurt her. We know she was a horrible mother, but you usually won't hear Regina say it. Zelena brings up being abandoned fairly often. Although in Zelena's first centric, I got the impression that her foster mother loved her. Of course we don't know how long she lived.