Beyhadh 2 holi scenes were somewhat the same between Saanjh and Ananya. In beyhadh 1, when Arjun was about to apply color to Maya, Saanjh had smeared the holi color powder on his face. Arjun didn't do anything about it. In this season, when Ananya was about to spread the color on Rudy's face before Maya, Rudra stopped her. So this is the difference between Rudra and Arjun. Beyhadh 1 had a dirty dance of Saajun, while beyhadh 2 didn't have those scenes. The similarities between Ruan and Saajun is both are childhood friends. Both were delusional.
The difference is Arjun never proposed to Saanjh in the beginning. He was very cool when Saanjh got the proposal. Rudra was clear to Ananya that he does not love her. But he proposed to her because he realized his love for Maya but never wanted to love again. Also, he didn't know whether Maya feels for him the same way. The moment he got to know that Maya also feels for him the same way, he left Ananya at the mandap and married Maya.
In the previous season, Arjun proposed to Maya when he realized his love for her. She would have retained Arjun's love if she had kept in touch with Ayaan and helped him when Arjun was away from his family for Maya's sake. Ayaan would have supported Maya if she had kept in touch with him and helped him. In this season, Maya would have retained Rudra's love if she had not killed Rishi.