I'm looking at it as five books I'd make someone who is not familiar with the topic read:
I'd take out MacGregor and Young's books for sure, and maybe Joyce's too (though I'm partial to keeping it).
Being a history forum, I'll add Michael McKinley's Putting A Roof On Winter: Hockey's Rise from Sports to Spectacle, which as the title suggests, looks at how hockey grew to what it is, in a simple layman's terms.
I also want something that looks outside Canada, and will suggest an unconventional book, Hockey: A Global History by Stephen Hardy and Andrew C. Holman. They look at hockey with a wide view: not just the NHL or Canada or men's hockey, but international, women, minorities, and so on.
Lastly, I want to include something about the business side of hockey, so will go with Net Worth: Exploding the Myths of Pro Hockey by David Cruise and Allison Griffiths. This was published in the early 1990s and Bruce Dowbiggan (the author of this list) wrote an updated book on developments since then (which as I've noted before is full of errors, and honestly not good), but it still holds up. It shows that hockey is a ruthless business, and that the players were squeezed on all sides: owners, Eagleson, etc.