This is a pamphlet (i.e. not a fully-blown book per se) is a satirical attack agains "value-free economics" prevalent during the 18th century.
The "solution" or "reform" being advanced aims at decreasing the number of children of poor people by advocating eating them when turn one year old - and claiming that this is an optimal course of action both in economic as well as culinary terms. Or, in Swift's words: "A young healthy child well nursed, is, at a year old, a most delicious nourishing and wholesome food, whether stewed, roasted, baked, or boiled; and I make no doubt that it will equally serve in a fricassee, or a ragout."
Obviously one of the main points of Swift is that there is no such thing as value-free economics.
Was it good?
The pamphlet reads really beautifully and oozes the rhetorical style of the period. Moreover - and importantly - the author really succeed in demonstrating how an attack against a school of thought can be done wholly in its own terms.
The main take-away for me?
In addition to the above, for me there are two main take-aways. First, the pamphlet really calls - quite justifiably, I think - into question the possibility of value-free economics, or purely technocratic societal decision-making. In other words, whatever course of action is selected, it always - Swift seems to argue - is based on some set of values instead of being value-free.
And second, Swift underscores the power of humour and laughter as a strategy of opposing something. Namely, if one argues against or seriously criticises something, one, by doing so, affirms the credibility of the argument being criticised through the very act of criticism (i.e. the position being criticised deserves to be taken seriously). Thus, by laughing at an argument or a position, one disaffirms the position by not even taking it seriously. Laughter is powerful.
Who should read the book?
Once again, this one should appeal to everyone, but especially those who are interested in economics, economic history, political economy or political philosophy. But in any case, the pamphlet reads so beautifully that basically anyone can derive enjoyment out of it.
The pamphlet freely available on Gutenberg.org: A Modest Proposal