@Stephanie First and foremost: cleanliness. Almost anything else is tolerable, but a dirty listing isn't acceptable to me, ever.
Everything else is pretty much negotiable, as long as it's accurately laid out on the listing and it's priced accordingly. I stay places for a variety of reasons, and I (mostly) don't need anything super fancy.
Thoughtful touches are always appreciated, to make it feel like the host cares. I personally don't like it when it looks like everything in the kitchen in the listing is from a jumble sale or stuff that was discarded from elsewhere. I use the kitchen pretty much everywhere I stay, and I want basic, thoughtful tools that work. A friend said that If you ever want to know what kitchen gadgets are a waste of money, just go stay in an Airbnb, because you'll find every useless, discarded tool there. Sadly, often he's right. As a caffiene addict, some way to make a decent cup of coffee is also always very much appreciated, even if it's just a private room listing.
I stayed in an Airbnb last week where the host had set out chocolates on the towels: it was a small gesture, but it just kind of said "we knew you were coming and we thought of you," not just "give us your money and get the heck out".