First off, that was the most retardest way to get rid of a character. They can do all the bad in the world to you but somehow they die a sudden death - yeah, um sure, that really makes sense! So if they had started this whole Payal saga, they might as well have shown a better ending to her character. Have her suffer in jail or send her to a mental asylum.
What a nice shock it would have been to the Ranawat family had Aastha shown up with Sonu right at the time that Shubh's mom handed him the sindoor. I'm sure somewhere deep inside Payal would have forgave the family had the rest of the family came to know the truth about the dad and grandpas mistreatment toward payal and their grandson. Although her plan would have failed, at least they could have punished the dad and the grandpa. They are two biggest culprits. Everything happened because of them.
Hopefully this serial will end sometime SOON!