My anti-Rand gag reflex is kicking in as we speak. :lol As for your points:
In an ideal world, the guiding priniciple would be selfishness. The ideal person is proud of his pride, and relishes each day. The fundamental absolute of life, is to exist, or not.
If people were all selfish,
and that selfishness were carried to its logical end (i.e., you're not just speaking of being selfish in
some spheres while being selfless in others), society would not be able to function.
The problem with altruism is that the system punishes those who abide by it, and those who abuse it most, get the most benefit.
You're absolutely correct; this does not argue
for selfishness, however-- it argues for greater altruism in society, and stricter penalties for those who manipulate, exploit, and otherwise engage in unscrupulous behavior to further their own lot in life.
If one follows the code of serving the public will, or the greater good, the only reward is a disliking of all humans as they are now seen as parasites, and eventually, the "greater good" consumes the true altrusistic.
So all people who are altruistic become jaded, and eventually "dislike all humans"? Highly suspect reasoning. Also, please clarify what you mean when you say that the greater good "consumes the true altruistic." (sic)
The world would be a much better place that instead of doing what society tells you, what religion permits you, is to do what one wants to fully enjoy life on our short time on earth.
And what of those instances when one's "wants" come into conflict with another's "wants"?
Ideally, one would do whatever one wishes, as long as it does not infringe on another's right to live, and pursue their happiness.
Ah, but see-- you're already setting limits on the level of selfishness we can exhibit.

The fact of the matter is that a renunciation of certain "selfish" desires and ends is necessary for the maintenance of civilized society. Read Hobbes if you're skeptical. The constant give and take of communal life cannot be made to be all "take," lest we dissolve the bonds of society altogether.
Basically, instead of giving, as altrusim dictates, the only way to deal with other rational individuals is through trade, where both sides standard of living improves.
You
do realize that the concepts of altruism and "selfishness" aren't exclusive to the economic arena, right? "Selfishness," insofar as it is (lamentably) an integral part of capitalism, is all well and good in the economic sphere-- but what of other areas of life? Interpersonally (and in the context of the broader social framework), one cannot champion an ethic of selfishness and simultaneously expect others in society to eschew their own needs and desires. For instance, say you're selling a product, and I want it but do not wish to pay for it. I decide to bludgeon you to death and take your product for myself. What then?
Well, you'd quite clearly need to have codified law, and an enforcement apparatus (such as a police force) by which to dissuade people from committing crimes against you and to apprehend those who would. You'd also need an implicit understanding among the members of society that one is not entitled to another's property just because one desires it. The point to take home is that barter is not an island unto itself; it requires a vast support structure to sustain it. Since that support structure is
inherently based on self
less actions/ideals, it holds that the economic sphere should neither esteem nor countenance selfish behavior, lest it be grossly incongruent with the rest of society. Certainly each man should tend to his own success, but as a society we should strive for moderation and commensuration, and responsible, ethical behavior on the part of business towards the society which has protected its interests and allowed its very existence. And "ethical behavior"
cannot include espousing a doctrine of selfishness in the midst of a society which has made every accommodation for business by way of self
less actions.
Society sustains business, both explicitly (by purchasing its wares) and implicitly (by providing the support structure necessary for business to function), not vice versa. Hence, business should always work towards furthering the ends of the society which sustains it. Not necessarily overtly, of course, as each company cannot be concerned with the larger social context at all times, but in terms of the ethic it champions and the restrictions it is subject to by society/government.
Laissez-faire capitalism, of the sort advocated by Rand, is bunk; I have
never heard a persuasive argument as to precisely
why we should champion one set of ethics, and ask all people to be temperate (to a degree) and to renounce certain of their "natural" rights in
every other sphere of society for the
sake of that society, and then turn around and basically give
carte blanche to businesses to do as they see fit at all times. It's inconsistent, and would not lead to a functional society (of which business is but
one component, however integral).
You can see this in action all around you. As deregulation has taken root, economic stratification has increased and quality of life has deteriorated. Corporations are like parasites-- they take what they want, and once they suck all the blood from one victim (host nation), they move on to another in order to exploit them. They have no loyalty to the society which houses and protects and subsidizes them; their only allegiance is to profit, and even this source of possible leverage against their machinations (e.g., we could threaten exclusion from our market unless businesses played by the rules) is rarely used by our government-- a government that is supposed to protect the interests of the people, but instead protects the interests of big business. They seek their own ends while everyone else's hands are tied in that regard by the social contract. It's bogus.
If one wonders how one can have moral values without religion, or altruistic values, I invite you to read the article in the link below.
I'm well aware of how society can be moral without the input of religion. It cannot, however, function without a certain amount of altruism (i.e., selfless behavior), as has been amply demonstrated.
I'll pass on the Rand link if it's alright with you-- I've had about enough of her for one lifetime.