(speaking as a blue collar, twenty something, married man, though admittedly for only a year and change, without any children...yet.)
- the "natural/unnatural" argument does not strike me as compelling; as Keble pointed out, it seems to be human nature (even in it's most noble manifestations) to do that which is "unnatural".
- the ascecis argument for NFP doesn't seem right; I don't see how something which is being done for fundamentally mercenary purposes constitues a form of asceticism. While abstaining for periods to avoid
conceiving children can be difficult and even cause suffering, the same can be said of the struggles of basically greedy men who build "Fortune 500" companies, in their road/agenda for financial success.
My understanding is that Orthodox Christianity holds up an ideal; that ideal being a Person, our Lord Jesus Christ. This ideal has been incarnated throughout history in the lives of His Saints. A central part of that idea is unselfish, unmercenary love for God and all of His creatures, for this is how God loves. Most of us (myself included) are far from claiming a hold on such selfless devotion to others. But that is what we're supposed to be struggling toward. The Holy Gospels give us some very concrete examples/manifestations of behaviour to be found in those who have acquired such love; forgiveness of all offences, love of enemies, turning the other cheek when struck, thinking nothing of lending or outright giving of our possessions to any who ask, etc. This is why even the greatest Saints cried out for mercy until they breathed their last.
This question of contraception, is a species of a larger question; how much do pastors of souls tolerate (in terms of the regular failings of their spiritual children) from their flocks, before enacting varying degrees of discipline, up to and including barring them from the Holy Mysteries, even outright excommunication? A large part of this question is answered/informed by the Orthodox understanding of the Church as "spiritual hospital", with human beings basically being sick creatures. Given this, even punishment has to have (even in it's most extreme manifestations) the goal of healing, both the individual and the community at large.
People calculating their offspring doesn't exactly sound like a glowing endorsement of Christ's teaching on God's providence (His admonishment of those who do not trust God to provide for what is truly needful.) But then again, is the solution to this to almost totally (or perhaps even totaly) bar such people from the Sacraments? That would be a decision for those whose insight into what is beneficial for souls is far greater than my own, built upon the wisdom of greater souls still (tradition). Perhaps there is not one universal answer to this either - what might be helpful for one married couple, might do more harm than good for another.
I sincerely believe that a couple putting their trust in God, do not need to be fearful of their fertility. With that said, the truth is that fear does exist. It's a symptom of other problems, without doubt. Thus, in cases like that, it may not be best to be severe in this one area, while leaving their other problems untreated (why they do not have unflinching confidence in God's ability to provide, etc.) It's a very complicated thing, since people are complicated things.
Perhaps what is needed more than an "official position" on what various local Orthodox Churches are willing to "allow", is an affirmation of the basic sinfulness of treating fruitfulness as a curse, while admitting the possibility that pastors may not necessarily cut a married couple off from the chalice for failing in this regard.
Fr.Seraphim (Rose) wrote something that I think is valuable in this discussion (I can only remember the saying vaguely, not word for word.) In essence he said "avoid sin...but even if you really think (though incorrectly) that you must sin, and do go on sinning, at least do not do this one tragic thing; deny that you are sinning - for if that happens, then all is lost." Obviously, if one attempts to white wash their short comings, or jesuitically deduce ways of justifying their variant of iniquitous behaviour, they're cutting away the possibility to improve themselves. A lot of this goes on in the discussion/debate of this topic; all or nothing "solutions" being offered, no one wanting to say that on this topic (as it is with so many moral issues as far as the Fathers are concerned) what is most damning: the ideal is incredibly lofty, we're obliged to struggle towards it, and almost all of us fail on a regular basis.
As something of a post script, I'd like to defend the Fathers and all of the "backward", crusty, celibate, (and perhaps most hauntingly of all for some on this forum) male monastics have to say on topics like this (and human sexuality in general). They're right. Sure, you'll find unbalanced people everywhere (including monasteries), but what they (and not just they, but great Fathers) say when discussing this matter is the ideal. That is how it "ought" to be. Pastorally, what the Church will tolerate (hopefully, only for a time) can often be a different matter, but they (the monks) are right. We shouldn't be using our "marriage rights" during fasting periods, the time leading up to receiving Holy Communion, should trust God to determine the size of our families, etc.