I’m sceptical of some of the claimed cost savings of reusable nappies that I’ve read online. For our first child we logged every nappy change for the first four months and it worked out under £15 per month. We used mostly Aldi Mamia nappies but got a trolley load of Pampers ridiculously cheap when Netto closed down so I guess if you paid full price for brands you would save significantly more by switching to reusables. There are definitely environmental reasons for ditching the disposables but financially it’s not that clear cut.
My top tip for saving money and time is to get on the batch cooking. We always have tubs full of a variety of meals in the freezer ready to throw in the microwave and serve with rice/pasta/potatoes/whatever. Once your child starts weaning you can batch cook their baby meals too and freeze small portions in muffin trays.
I’d also not rush into buying gadgets before you know what you’re actually going to use.