That's all fine.. but none of that, as far as I can see, is derived from a belief in atheism, rather it's derived from you examining your conscience as any decent theist would do also.
Atheism does not encourage mankind to see equal value in our fellow beings, yet theism does, quite insistently.
Ehhhntt!!! Dead wrong!
If there is anything that distances humanity more from itself than religion, I cannot imagine it. From the farcical self- and other-hatred represented by original sin (intrinsic evil) to the devaluation of humans below that of a delusional webwork of lies. This is precisely what I am talking about when I speak of philosophies being tools, not truths. Philosophies exist to serve people, not the other way around. As tools philosophies can be powerful servants. As "Truths" philosophies can be enslavement machines.
Atheism remains silent on the matter, as it does on so many other important issues.
Thus those who are atheists will be less likely to be regularly exposed to the positive moral exhortations typical of theism.
That doesn't mean any individual atheist is bound to be more immoral, but the general influence will be in that direction.
Again, entirely mistaken. One can derive or acquire one's values from any of a number of sources. I see no particular reason why one should derive one's values from the webwork of lies and anti-humanity hatred that is religious truth-think. That so-called morality is a means to an ends - the subjugation of humanity to one philosophy, which cannot but be a serious error.
Better, I would say, to recognize that one's values are a result of the persons around you, the reasonable expectations you have of them and that they have of you and attempts to try to universalize these, and do away with the nonsense of "objective morality" grounded in a psychopathic monstrosity.
Positive secular values? Longer life spans with better quality of living, progress in terms of human efficacy, a better tomorrow for our children. That some cannot (scratch that!) refuse to see these things as positive without the gawd element is not a sign of an atheist's failure - it is a symptom of an attempt to define all things in terms of gawd and render meaningless anything that does not derive from it. It is a shoehorning of positive human traits into the wrong shaped slots.
The future is not meaningless. Children are not meaningless. Other people are not meaningless. We can perceive them as having value in themselves, entirely without gawd. In fact, we must do away with gawd to allow their value to become clear, rather than subordinate to some miscellaneous, anonymous, third-rate, ill-conceived, cynical, anti-human dogma. People are more than cogs in a dogmatic machine; more than a means to an end. It is not the atheist's failure that the religious cannot (will not) see this.
Atheism doesn't necessarily lead to these particular values, but without it we don't even have a chance of reaching them - the lie of "Truth" gets in the way.
In reality, religious thinking is so rife with contradictions and incoherencies that it does not, in fact, consistently prohibit or encourage anything at all. To those who say that without gawd, there is no guiding light, the only proper answer is to point out just how dim that "light" is, that light that advocates murdering children and killing non-believers on sight, indoctrinating the young with self-hatred and terror, covering up sexual abuses, the list or exemplary morality goes on and on and on. If that's morality, it's time to leave morality by the wayside and come up with something better. There's a reason that "light" is so dim; it is not founded in humanity. It is the subjugation of humanity - the sickness that infects us when we elevate philosophies to Truths and think them more important the people.
It's time to do better, and we can do better...but not until we have pulled ourselves from the quagmire of superstition, horror, hatred, cruelty, self-loathing and subjugation of humanity that is religion, and the symbol and icon of that anti-human thinking, gawd.
Atheism is the first step towards a morality for living, breathing, loving, multi-faceted, full-living-colour humanity, not just abstracted pawns in a two-dimensional black & white dogmatic scheme.
Religion qua pre-packaged morality is a deliberate failure to accept responsibility for one's attitudes, not just one's actions, but one's attitudes. How many more young women have to die of cancer caused by HPV before we realize that the "high road" is a dead end?