Rift between Arjun and Madhu
As Arjun gave mixed signals to Madhu, now it seems like they'll get committed. Then how will Rina come into the picture?
It won't be nice if Arjun leaves Madhu for Rina. Only a rift between Arjun and Madhu can make this possible.
Madhu's character is getting worse week by week. So I think she'll cross boundaries to make Arjun angry (which she already did with Sid), this time a bit more. Then they'll part ways. Arjun and Rina realising their love for each other will be a separate story line I believe.
Thoughts are welcome.