I'm honestly not bothered about a welcome pack of fresh food. I don't generally expect the cottage to supply consumables. But what I'd like to find in the kitchen would be basics that keep well but you only need a little of for a week or two, like salt, vegetable oil, mixed herbs. Washing-up liquid. A couple of extra rolls of toilet paper and a couple of dishwasher tabs. I'd also want a list of these things on the website, so I'd know not to pack them.
Equipment-wise:
A full-size fridge-freezer. So frustrating to go on holiday for a week, and have to waste time on food-shopping because there's no space for a week's food.
An empty cupboard for food. So many places have cupboards and cupboards full of glasses and mugs, yet nowhere decent to store what we bring with and food.
(I really do not need a whole cupboard-full of 4-5 different styles of glasses! A 6-bed house aimed at families with children does not need 6 beer mugs, 6 lager glasses, 6 flutes, 6 red wine, 6 highballs, etc etc.)
A set of sharp knives - serrated usually hold their edge acceptably. Most importantly, a 6-7" veg knife, a 7" cooks' knife, a bread knife.
Decent veg peelers, both styles.
Pans with matching lids.
Plastic chopping boards. A wooden bread board looks lovely, and is fine at home, but you never know how previous guests may have used it - I don't want to cut my bread or my salad on a wooden board previously used for cutting up raw chicken.
A freestanding stick-thing to put my kitchen roll on. Not a dispenser fixed to the wall, because not all rolls are the same size, and, in any case, with dc I want to have the roll close at hand during meals!