It think you have the main options. You could replace holiday with break, especially if it's a short holiday. But what you have are the usual phrases, I don't think there are any other commonly used ones. If you want to make it more interesting, normally you'd just add your own comment e.g. if talking to a colleague you might say "Enjoy your holiday. I'm sure you'll be thinking of us". The second part being a humorous addition because obviously they won't want to be thinking about work. But again, I don't think there is anything particularly standard.

" Enjoy your/the holidays." I have heard it more often.

enjoy your time?