Now my opinion!!
First of all ShivIka are the only couple right now whose story is getting proper and progressive development. It is slow, yet steady and also very beautiful for the fans...as they are getting a complete combination of comedy, intensity, angst and other basic elements.
IshKara story hasn't even begun yet properly, yesterday was the beginning, for me! Ishana is a con. She wanted to separate for Riddhima and Omkara for her selfish purposes, for money. She is not a good, all pavitra character, like Anika. She is flawed. You can't expect her to be all goody. And she blasted because Om had said against her family. Nobody would bear that, and nobody is perfect!!
She was going away, admitting her wrong, but when he said stuff on the way she has been brought up and her family, she will not bear it! There isn't anything wrong in that. And the reasons she gave, were bang on! Now there story has begun, and if they get a proper storyline, I am sure, all will love them...if!
Even I don't like RuMya as a couple. I don't like to watch those scenes, those love angel ones and stupid fights. I love Rudra as a character, he is amazing...but the couple don't go well with me too!