I believe KuKu have potential but Kunal really needs to go through hell for Kuhu to forgive him.
Even today, I was a bit annoyed when he said 'I was there with her when she needed me but she left me'. It was a very selfish analysis, IMO. She fainted due to an allergic reaction which he unknowingly caused. She was not even conscious when he was 'there' for her. Why should she be grateful for him being there when she was sick? Isn't that basic humanity? I really hope he doesn't throw this in her face as him doing a favour for her.
KuKu will arrive for me when Kunal the soldier disobeys Meenakshi and is actually willing to put everything on the line for Kuhu, like he put Kuhu on the line for 'family'. Don't want a watered down redemption because that happens with every male character ever. I want Kunal to fight for Kuhu and not merely grow affectionate towards her due to circumstances.