I think they never imagined the character to be such a hit and the novelty factor of having a well-written ML character helped a lot. I don't mind if he's the one to unravel the details, just get it done. I know ITV usually has female-centric stories but in this case I would prefer they stick to their current approach. It would be much more believable and better for TRPs.
Also, with the supporting characters, I understand they need them but must they be so annoying? All shows have side characters but smart writers know how to enhance the story through them. Forget other shows, even here, look at how much we're appreciating Farhad and even Harish from day 1, who aren't technically Raghav's family. It's because they help move the story forward but are not written as plain and stereotypical characters. I can't say the same for the Deshmukhs. Also, I believe that not having more of her dada and vahini was a big miss on the writers' parts. That dynamic may never explored in the show, which is a total shame. Siddesh is a good man and I refuse to believe he would stop being invested in his sister's happiness, unless we discover difference facet of his later, if ever.
I think they did anticipate, cause initial promos me, they kept his angle a little hidden. Cause focus was on the widow remarriage bit. It was like her worst fear came true with Raghav Rao. But once they saw his popularity because of Sai Ketan's work, they are now utlising that as the pivot on which rest of the story will run.
Till now, it was all about Raghav and his trauma. Now it will be about Raghav getting to know about Pallavi and her life. Kyunki Raghav ke life ka mess to sort ho gaya with his family coming to live with him. Now he has a lot of time figuring out how to deal with his "supposed' wife.