I could probably offer better advice about prefolds than wool.
DH actually knits-but not a huge amount of free-time, so DS was in Thirsties covers most of the time.
As long as there is no sensitivity to wool, it is fantastic!!
(I say because I am HORRIBLY sensitive to wool, but luckily DS was fine with it. Just watch for redness and scratching.)
Prefolds rock! Not everybody uses them, but I LOVE Snappis. I was always able to get a super-trim fit with them. Prefolds allow you to try a huge variety of folds to meet your needs-boy vs girl, heavy wetter, exploding poop protection(jelly-roll fold was the best for us). It's easy to use an overlarge prefold on your baby, if you need to save some money by not splurging on newborn-sized dipes for maybe a few months of use. We did this by folding the top edge of the diaper backward until it was short enough in the front-this also created a nice "shelf" in the back to help prevent explosions.
Then of course you can fold up an extra one and use it as a doubler.
If you are used to sposies for a newborn, know you need to check VERY frequently in the early months to change wet dipes asap. My son was a heavy wetter, granted, but I checked him about every 5-10 minutes and more often than not, he'd wet about every 15.
Not sure what else helpful I can say about prefolds, since you obviously know the basics of CDing. Have fun!!
