1. Sure, if the physical constants & ratios were different than they are, then things would be different, and life as we know it could not have gotten started. But we have no idea what all the implications would be, on a macroscopic scale, if the constants were different. We can say, "if this ratio was different, then stars as we know them could never form." Or, "if this constant was different, stars could never produce elements heavier than helium." But who knows if carbon-based life is the only possible type of life? And if, say, electromagnetism was the dominant force in a universe, who knows what the menagerie of elemental particles & resulting chemistry would look like? We have a sample size of one, and only the vaguest notion of what the other hypothetical samples might look like.
2. The extent to which we're impressed by how different things would have turned out if the ratios were different depends soley on how big our imaginations are. So the ratio of constant A to constant B is exactly 1.28485:1, and if it were greater than 1.28486:1 or less than 1.28484:1 then something on the macro-level would be very different than it is today. Is that remarkable or not? Well, to someone who can hardly imagine the ratio being less than 1.2:1 or greater than 1.3:1, the fact that it does fall inside the narrow range that it does is much less remarkable than to someone who can imagine the ratios being 100:1 or 1:100.
The problem is, anytime we learn about what causes some phenomenon of nature, we learn why the phenomenon is what it is, instead of being else. We learn why it never could have been any other way in the first place!
So any astonishment we might feel at the narrow range of physical constants & ratios is really an artifact of our lack of knowledge, coupled with our imaginations.
3. If the multiverse theory is true, then much of the rationale for being astonished by our universe's seeming to be designed for life as we know it goes away. So the author thinks it's just wishful thinking for atheists. But as I understand it, the multiverse theory actually pops out from the equations of standard cosmological theories.
This is a case where the author should have spent a little time on oppo. research to see if maybe these atheists had any decent reasons to think the way they do. If he had, maybe he could have come up with a counterargument that we might be impressed by.