Heaven is exactly what our imagination needs it to be. In heaven, where all people really love each other, there are no inhibitions, or need for them. This allows a freedom and happiness that people on earth can't imagine. People don't go to heaven because of their good deeds, or because they believe this or that, but because they fit in and belong. It's what you are that counts.
All souls evolve.
Souls can choose to remain in heaven and operate on a particular level for eternity if they desire. After death, each soul has to rise as best it can through a hierarchy of heavens and face the increasingly difficult challenges posed by the guardian angels of each level of heaven. Everything is kept pure by God. Our deceased pets appear in heaven the way we remember them, only younger and more vital. We can communicate with them telepathically.