Hi Jessica!
Congrats on #2! I am new to this board....I have CD 2 kids....Sewing will help you save $ even with CD (which saves $ too) I only CD DD from birth, DS was from about 9 mos til he learned potty. If you need to ask me more questions after you've read some of my answers feel free to PM me.
Should I start with Prefolds and a cover and then go to A-in-1 (or pocket) (using the prefolds as stuffers)? If you are diapering a newborn I would use prefolds and covers....then when the LO gets to be about 15 pounds or so they will fit in the one size pockets.
How many do you recommend? 14-18 for a newborn (prefolds) and 6-8 covers......you can drop the number down to 12-16 at about 5-6mos depending on the laundry schedule. Snappies are great for closing diapers on wiggle newborns....or you can just lay the prefold inside the cover.
Is it really gross to clean them? not my way

I keep a dry diaper bucket (trash can) with a lid....I only rinse #2 before they go in it(we have a sprayer for that attached to the toilet)...on laundry day I wash the diapers first on cold w/ nothing, then run a whites cycle w/ detergent & oxi, then run a 3rd cycle with just water....u can line dry or put them in the dryer. While they are running I hose out the bucket... outside with bleach.
Do they leak more than disposables? not as long as you wash properly (no fabric softner it makes diapers repel liquid) actually one reason I went to cloth was DS could pee through anything...cloth worked better for him.
And what are some good patterns out there? I probably won't buy a snap press, but could do pliers. Trimsies have a sized diaper pattern.....the Darling Diaper Unlimited pattern has a free newborn pattern you can test out, another popular free pattern is "Rita's Rump Pocket" (I think its a one size). The Darling Diaper has every kind of diaper/ many sizes in one pattern....If I decide to go for #3

I would buy it. I used the Very Baby diaper cover pattern with my store bought prefolds w/ DD.