I would have much the same list as @Emilia42.
I'd add to that, that the guests answer any messages I send them in a timely fashion and respond to all I have written rather than just part of it.
I like guests who aren't shy to ask if they are confused about something, rather than just go ahead and use something improperly. Like the European guest who asked for clarification about what she was expected to sleep under and over, as she was used to just a duvet, rather than a top sheet and blanket. (I'm not referring to guests who don't bother to read provided instructions or need constant hand-holding).
A guest who has obviously put a little time and effort into writing a review, rather than just dashing off a one-liner or not bothering to review at all (That's one way a guest is showing appreciation).
And because I don't use IB, a friendly, informative initial message when they request to book is a big plus and tells me a lot about what sort of person this is. It's important to me because I'm a home-share host, so getting the impression that this will be a nice guest to have around puts me at ease with the booking.
And of course, guests who do generous, appreciative and considerate things like arrive with a small gift, or ask if there's any small thing I need that I can't get in Mexico (yes, several guests have asked me that and brought those items), leave me a thank you note or give me a picture they've drawn, or bring home a bottle of wine to share, are awesome.