I have met atheists who are high in the light and full of goodness and I have met Christians who are dark, ignorant and full of malice. Truly, what one proclaims oneself to be is often greatly removed from what one really is.
One's light quotient depends upon living with an open heart and viewing the world with benevolence and compassion. Self-deception is all pervasive. Very few people can look in the mirror and receive an accurate reflection of who they truly are. For this reason many people, upon death, are surprised at the realm they end up in. "I was a good Catholic", they think. But the true contents of our consciousness are often not what we wish or believe them to be.
Our afterlife reality is a reflection of our mind before and after death. It is up to us to create thought forms that are beautiful and reflect the light of the Lord rather than the darkness and ignorance of the human ego. This is done by allowing those around us to live as they choose and for us to only view the world with love and compassion, not judgement! Yes, we can set a good example, but it is up to other people to choose whether to follow it or not and it's not for us to attempt to force them in any way!