We did cloth nappies so all changing was done in the nursery where the nappy bucket was. The bathroom is next door to any rinsing/flushing was simple enough to do.
I really didn't see the point of having more than one bucket on the go (also meant more than one bucket to disinfect every day).
Batch cooking for the freezer was a life saver. Bolognese, Lasagne, Meatballs in tomato sauce, veggie curry, fish pie, Chilli con Carne, Casseroles all freeze well.
Also make a list of very easy to put together dinners (things on toast, jacket spuds etc) as postpartum jelly brain can just make these things difficult to think of. It sometimes helps to have a list to jog you.
Stock up on all sorts of household stuff so you just don't have to think of any of it for a good while
Loo rolls
Washing powder
Kitchen Foil
Washing up liquid
Dishwasher tablets
Kitchen rolls
Bleach/disinfectant
Shampoo/conditioner
Also a decent stock of store cupboard foods
Tea bags
Coffee
Sugar
Tinned tuna
Beans
Mayo
Tinned tomatoes
Dried pasta
Rice
Cereal etc
For you:
Lavender and Tree tree oils (add 12 drops to a shallow 'sitz' bath to aid healing perineal stitches or tear daily). Alternate between the two.
A small stash of your favourite chocolate
Two bog standard V shaped pillow and spare covers for feeding (however you choose to feed, makes it more comfortable and secure), one to be kept upstairs and one downstairs. I borrowed a friend's fancy breastfeeding cushion filled with microbeads after DC3 was born and didn't think much of it. It cost about six times more than my standard V cushion and I much preferred mine. I also took it in the car with me when out and about and had to do a feed in the car, made it much easier.
Hand cream at every sink and in the changing bag. So much hand washing! My hands were raw without re-applying hand cream.
For the Baby;
Braun ear thermometer
Sudocrem
Calpol (just have it in and ready for the first vaccinations)
Metanium nappy cream (big guns for nappy rash, have it on stand by)
A carrycot for your pram to be used as a daytime bed downstairs
Isofix base for your car seat. Expensive but worth every penny.