Every family is different. Every baby is different. Nobody can tell you what you will think is a lifesaver, and what you’ll put in a garage sale unopened.
Having said that… here’s what we actually used.
Bedding: a crib with a mattress, a waterproof mattress cover, three fitted sheets, and sleep sacks for the baby. And one quilt to keep her warm in her bouncy seat. No bumpers, positioners, stuffed animals, etc.
A “travel system” with car seat base, stroller base, and bucket carrier that snapped into both.
Half a dozen outfits, assuming you do a load of “baby laundry” every 1-2 days.
Half a dozen burp cloths. She wasn’t much of a spitter.
Diapers, wipes, a small trash can with a foot-pedal lid, and lots of plastic grocery sacks. Diapers go out once a day, at bedtime.
Pacifiers–as noted, have several shapes on hand.
A large absorbent pad. I slept on it before she was born, in case my water broke in the night. After she was born, it was her base for Naked Baby Time, which inevitably became Peeing On Herself time.
Baby wash, baby washcloths, and a small baby bathtub. Newborns are too floppy and slippery to bath in the big tub. A couple of baby towels (they have a softer nap than adult towels).
A fan, to provide white noise in her room. Made us less likely to wake her up. Also: blackout curtains in her room. She didn’t nap at all until we got them.
And lastly, the thing about which I have the strongest opinions, due to my own gruesome experience: a package of half a dozen ready-feed bottles of formula, no matter HOW virtuous your wife feels about breastfeeding. La Leche League out to be sued out of existence; they are definitely lying to you. Have some formula ready so you don’t have to feel the way I felt, that morning at 3am, when I had nothing to give my hungry newborn.