I think this is a good value type of list, but how are you buying the produce, frozen is often cheaper although some caveats apply, tins are sometimes cheaper again some caveats apply
Dried pulses are the cheapest but require pre planning and long cooking for some, you might not want that
Big packs of eggs can be good value and something like a savoury bread and butter pudding with small bits of bacon, cheese, eggs, veg, baked in the oven
Are you trying to put things in the oven all together so that you save heating costs? Or use the airfryer as much as you can which is a bit cheaper to run.
How are you doing the soup, are you cooking down the bones for stock, really wholesome, good flavour, good nutrition and cheaper and healthier than buying soups, particularly fresh soups which can work out pricey. But you need freezer space. Also the cost of cooking them down
Smoked haddock instead of the cod and salmon? Big flavour and a bit cheaper if you buy 'bits' in Aldi or Lidl, one of them
Tinned fish like pilchards and sild, on toast, with cheese on top, gorgeous and cheap and very healthy.
Cabbages are very cheap, dont get hooked in by the cavalo nero, basic good cabbage, you can shred it, put it in chicken stock in a baking dish/enamel dish, with herbs, onions, perhaps white wine if you have it and bake it down, crispy on top and creamy and unctuous underneath. Cabbages are powerhouses of nutrition.