Oh yes a king-sized bed, and a headboard - stayed at a place last year where we couldn't sit in bed with a cup of tea, despite the gorgeous view over the beach!
Comfortable seating and enough for everyone to lounge. So if you have beds for four people, then lounging space for four people. No leather or obviously second-hand/inherited furniture. A grotty sofa covered with a throw is still a grotty sofa.
Loads more towels than are usually provided. Quite often you get one hand towel and one small bath towel per person. You can't do much with a hand towel. I can't wrap my hair in one. If I could have my way it would be three bath sheets per person, at least one of them a large one - tiny towels remind me of the sixties.
Bedside tables and lamps and plugs for phones/laptops by the bed. Not behind the bed.
If there's a woodturning stove and it's winter, then provide fuel. By all means charge for it but provide a decent amount and can it be dry wood, like you'd have in your home? Not damp logs that aren't going to burn.
A tv that comes with one remote control for everything and also instructions. I can never make head nor tail of holiday home tvs. No big deal, I don't watch a lot, but I do always feel like asking for a bit of money back if nothing works easily.
Here's what I personally would like: yes to super fast wifi but if the renter asks for it to be switched off, a set-up that means it can be toggled. Or just absolutely no wifi. I like to not bring devices with me and have a proper holiday reading books. Mind you last time, that backfired because DH brought his own hotspot, the bastard.
And last but not least: if people are paying upwards of £600 a week, often much more, don't make them clean. "Leave this house as you found it" - actually, I am paying for this house, you're not lending it to me out of the goodness of your heart, it is a financial transaction!