The diapering market is pretty fickle.
I make wipes out of the following materials:
hemp stretch french terry
For fitted dipes:
hemp stretchy french terry
I don't care for AIOs, so I don't bother with those.
Nursing Pads can be made out of anything, but the backing needs to be waterproof.
Slings I make out of thin cotton, but we live in FL and there is rarely a call for thick slings.
Good luck! It's an addictive prospect, sewing dipes is...