I agree with Pope Pius XII. In his famous "Allocution to the Italian Midwives" he warned that any use of periodic continence which was not justified by grave reasons was "a sin against the very nature of married life."
Then in his "Address to Large Families" he encouraged Catholic families to accept children from God "in whatever number He chooses to send them."
If agreeing with Pope Pius XII makes me a "providentialist," then fine, that sounds like a pretty complimentary term. And as for those using NFP being "inferior," their consciences can tell them if they are really justified by sufficiently grave reasons. But Pope Pius XII had no problem denying any equality between large families and those reduced by family size limitation:
Large families are the most splendid flower-beds in the garden of the Church; happiness flowers in them and sanctity ripens in favorable soil. Every family group, even the smallest, was meant by God to be an oasis of spiritual peace. But there is a tremendous difference: where the number of children is not much more than one, that serene intimacy that gives value to life has a touch of melancholy or of pallor about it; it does not last as long, it may be more uncertain, it is often clouded by secret fears and remorse. It is very different from the serenity of spirit to be found in parents who are surrounded by a rich abundance of young lives. The joy that comes from the plentiful blessings of God breaks out in a thousand different ways and there is no fear that it will end.
Why are you to glorify God? - Because he made me and takes care of me.
What I hate most about NFP is that it requires abstinence when the wife's wondrous libido is at it's glorious peak. The Creator designed the reproduction system to give pleasure and create children. It's pretty marvelous the way it works. It's so much better than the ways that any of the other creatures' work. It's sad that depraved mind seeks ways to foil such a benevolent and ingenious system.