After the 18 year time leap on pkg...things will have changed...
Possible future characters:
Megha: (Rimjhim's daughter) Megha will return and will be played by Narayani Shastri in double role. She'l probably be a spoilt brat and she'l hate her real mum Rimjhim for killing Malini (who raised her). Megha will probably be quite modern and Avinash and the family will barely be able to control her wild ways. Megha will be quite close to Yashoda (in the maternal sense) as she always has been.
Soham: (Yashoda's son) He'l probably return as a handsome young lad. Love his mummy and daddy. He'l be close to sister Megha.
Vishal: (Kaveri's son) He'l probably be alot like his deceased father Pratik..i.e. gentle, understanding, very good natured.
Om: (Yashoda's son but raised by Jayanti as her own) Will grow up and think of Yashoda and Rakesh as his Mami and Mama... but will eventually find out that they are his real parents.
Shweta son/daughter: (Avinashs son/daughter when Avinash thought he was Anand) Will probably make a return to the show as an antagonist/villain..who wants his/her rights from Avinash. He/she will probably be against Megha.
Sameers mischievious niece and nephews: (a girl and two boys).. they may make a return to the show as grown ups.
Megha's love interest: some handsome guy
Vishal and Soham will also have love interests
Other possibilities:
Raj's daughter: (Raj is Rimjhims friend) Unlikely
Pihu: (Yashoda's daughter who stopped breathing at birth then died): Its unlikely she'l return but ..you never know in indian serials..
Malinis baby: (who died in the accident): But..u never know...the doctor may have stolen it for all we know
Rakesh was sleeping with Mohini..that may have led to a child that Rakesh doesnt know about
Durga's daughter Guddi was pregnant...this child may also make a return. She would be a tad older then Megha