I love the show specially the realization of love and various relationships. People seems to forget that usually two people do not fall in love simultaneously. One may accept feeling in love before the other one. In this story, Viaan is rich and have a staff to take care at home and not so much responsibilities at home but seems to be in love for the first time (like Ehasan said first love is always Euphoria)
On the other hand, Katha have tons of responsibilities and she has just gone through ordeal of her son's medical emergency, work stress situations, etc. In this situation, last thing on her mind is handling his boss being in love with her. At this point, all she cares to be happy with her son and finish project at the workplace. It will struck her one day that she is entitled to have that feeling again.
There is never right or wrong way for being in love, method wise or time wise. I have seen plenty of real life situations and came to conclusion, every love story is different. Even the most intelligent/sophisticated people end up behaving in silly way because they seems to lose control (told by friend madly in love).
One thing for sure, consistency in love most of the time wins as long as there is no feeling of hate/repulsion.
I like all the actors in this show. I agree it would be nice to show Katha opening up to Viaan (like hospital scene) about ONS specially before they start their journey together. They have shown Katha and Viaan, very honest with their feelings. Since open communication about feelings have become become rare in social media age, it nice to see in this show.