A wrap-style sling for the newborn and small baby stage (so comfy when they're little and great for late afternoon nap time if they're cranky) and a soft structured carrier like an ergo for small baby and beyond (the one I used for my six year old is still being used with my 21 month old).
A Bluetooth speaker/sound machine to play white noise through when he wouldn't sleep.
A co-sleeping bassinet like the Arm's Reach - straps to the bed so they're in their own space but right beside you.
SwaddleUp zip up swaddle thing when he wouldn't sleep. They have their arms up by their head (look like snow angels in them) but aren't able to whack themselves in the face.