Hi op and congratulations!!
Just to say, a planned section and the recovery from it can be super different than from a crash section. So hopefully you'll find it easier this time round.
I had a planned section. Just needed paracetamol and ibuprofen as pain relief and peppermint tea. That was sufficient for me but I did notice that if I didn't spread it out well enough I'd start to get quite sore so make sure you're timing it when you get home and trying to stretch it across the day! The more rest you can get on the other side the better. I did too much when dh went back to work in week 3 and pulled stitches.
For packing, I brought a nappy bag for ds with everything he'd need in it. Brought 2 sizes of clothes (newborn and 0-3 incase he was bigger/ smaller than expected).
A case with all my stuff but I put my slippers and dressing gown on top so that I could quickly grab them after changing for delivery. Especially as you need to walk to the theatre and the gowns are see through and open at the back and walking in stockings can be slippy.
I then had everything else I'd need on the bottom. So things like a long phone charging cable and battery pack. Snacks as I was really hungry after but I'd missed lunch so had to wait until dinner. A cushion to put between your tummy and the seat belt on the way home. A few button down nighties because then it was easy to open for feeding/ wound checking/injections. Bluetooth headphones so i could watch shows on my phone. Leggings and a big zip up hoodie and slip on sandals so I could dress myself really easily and be comfy. High waisted pants/ leggings.
I had harvested some colostrum in advance so I brought that in a cool bag. Plus maternity notes, copies of my birth plan (you can make one for a planned section). A big water bottle as I was really thirsty and you have to pee a certain amount before they can discharge you so the more you drink the better. An extra pillow/nursing pillow is a good shout.
Have some stool softener at home waiting on you to help when you need to go and plenty of support lined up especially since you already have a child.