Before I begin, I would like to say that I am in NO way supporting what happened with Ruhi. Having said that here's my take
Both Yuvi and Rehan are total kameenas. They are totally tharki and eye almost every girl as a sex object. But they have a few reddemire qualities.
YUVI
As people had discussed before on this forum, Yuvi loved Mahir. Even if he is shown as a selfish fellow, there is no doubt the he loved Mahir. He also had fair amount of love for his mother. Adi is a total kameena. But Yuvi always loved Adi and Pratham. Despite being his half brothers he never differentiated between Mahir and them.
REHAN
Whatever their faults, the Mittal siblings had love for each other. Anu was genuinely worried when Rehan failed to show up. Also the reason why Rehan went to the haveli in first place was because he thought that Bella was in danger. He thought Vish was going to harm Bella and so he followed her.
At least these two characters had a chance of redemption.