Overall I think Billu Barber is an average movie. Its a kind of movie you will watch once happily, but will not remember after a while, or will not put an impact in your mind. The emotional extraction process of sympathy in audience's mind is something director's thrive on for the success of the movuie. But along with that, some naturalistic acting is required as well. Some of the dialogue throws or sequences are too predictable like the 90s movies. SRK is going down-hill movie by movie. He has to change his outlook, and performances, and of course his own mental state to hang in for longer time.
Ir(r)fan Khan tried to deliver with his natural talent and he has succeeded in that level. Rajpal Yadav is slowly approaching towards another Johhny Lever in making. He had so much potential, now he is turning himself into a no-man's land. Not a serious actor, not a comedian, just irritating.
Anyways, hoping for better productions from Red Chillies in future.