While this is amazing for you it should be taken with a note of caution from readers. This may happen or may not if you decide to have kids. There are many parents who are unhappy with their families and feel trapped. Before having a family do research into it beneath the pop culture "transformation" ideas. This transformation may happen and you may be incredibly happy. It may not and you will feel trapped. Have children because you want to, not because you need them to change your life.
I love my son and I love playing with him, but it did not change my life in the way GP describes. I try to be present in the moment, and I work part-time to spend more time with my son, but it's not rare that I feel a bit impatient for him and his mother to go to sleep so I can build stuff.