PN is getting kid ready for kindergarten and become more independent. Playgroup is still very important as parent and kid build up trust during the class. The trust relationship is vvvvery impt for the child development.
PN is cheap. Playgroup is very expensive if you compare 5 days per week. PN teach many things and the baby become more dicipline and independent, obey instructions.
But PN is very less related to the chance of K1 cause when you interview for K1, the babies only study for short time in PN. The K1 kg will usually not consider which PN you study. They will only see babies' capability and child-parent relationship.