I take offense at the assumption/implication that atheists are unable to be equally good people as religious people
A true religious person is more high-minded than an atheist because religion urges people to be well mannered, and deters them from being wicked and from committing such crimes (but still atheists can be very high-minded.)
Those who commit crimes, claiming that it's their religion, are very mistaken! All the divine religions forbid people from doing immoral deeds.
-> effectively saying I'm not as good a person as you simple because I don't believe one or many supernatural powerful creatures exist.
First, I'm not simple, :) and second God is not a creature! He is the Creator of creatures. It's not a fact that's beyond the reach of logic. It's not an imaginary fact that God exists, nor is it believed in just for a person to feel safe because a "supernatural creature" is protecting them. It's a fact that God exists with many proofs. Islam has proven so far many facts stated through the Holy Qur'an. And as you know, the Holy Qur'an was sent to the Prophet of Islam, Muhammad peace be upon him, more than 1400 years ago, yet scientists today discover new facts, then we realize that it is mentioned in the Holy Qur'an. That means that God, Who created us and knows everything about us, does exist because these facts were impossible to be discovered at the time when Islam started to spread in the Arab Peninsula.
Atheist have more reason to want to be good people, to be nice to others, to make the world a better place because there is no afterlife, there is no future happiness to make up for suffering today, this life is all there is so we have a duty to make it a good life for each and every person.
I say again, an atheist can be very high-minded, but when they become religious they'll be better-mannered. Islam teaches people to try very hard to improve their knowledge and to make the world a better place to live at any cost because there IS an afterlife.
Islam orders people to learn how to live a better life. If you study the Islamic history, you'll realize what I'm saying, and you'll see and be astonished by how many Islamic scientists have brought science forward. Until today, science depends on many achievements that were made by those scientists.