After The Lion, the Witch and the Wardrobe, The Magician's Nephew is probably the best of the Chronicles of Narina. Perhaps even the best.
What you see and what you hear depends a great deal on where you are standing. It also depends on what sort of person you are.
Chronologically, it’s the first in the series. To the extent that we actually get to see the Genesis story of Narnia. From nothing, Aslan breathed life into the world, long before any of the other adventures we’ve come to read about ever happen. On top of that, we see hints of innumerable other worlds, get a bit more backstory on the Witch, and meet a whole new cast of interesting characters.
It’s still not a super deep book. The good characters are Good, the bad guys are comically evil, and you know everything is going to end up all right. But if you take all that as a given, it’s well written and an enjoyable read.
Orderwise, I think putting this near the end is probably the right idea. You would have a bit more backstory if you read this first (as you would chronologically), but that’s not always for the best.
Onwards and The Last Battlewards!