Hi ladies
We all have our own preferences. For me:
1. No fancy outfits for a newborn. It's not comfortable for them, it's not easy putting on and taking off.
2. Don't over dress a baby. They overheat very quickly. So a vest is fine and the baby grow. If it's cooler, wrap them in a blanket. I personally love cellular blankets as they have breathable holes that result in baby not overheating vs the fleecy blankets.
My kids used to sleep in 'onesies'...so there really was little distinction between day wear and night time wear in my house. lol.
It was all about keeping the baby comfortable.
Newborn, depending on size of baby, they may wear for anything for a week to 6 weeks or longer. My daughter was 3.4kgs at birth, went down to 2.9kgs and she wore newborn for 6 weeks.
My son was 3.69 at birth and wore newborn for about a month.
I wouldn't splurge on newborn....I'd say about 6-8 onesies that can be rotated and washed. If your baby very small and will be wearing it longer...then invest in a few more pieces.
I am not a fan of the body vests with the side clips as my paed said when we hold baby, we press those clips into their skin and my daughter had little round marks all over (I felt like the world's worst mom).
You are going to change them often so try to get the onesies where it's easier to just get the leg out and not have to take the whole thing off.
If it's freezing outside I guess you can put socks on under the onesie. But always keep in mind that you do't want them to overheat. I'd rather wrap in a blanket for warmth that I can remove if it gets warmer.
Good luck! You'll get the hang of it, really don't stress about this