Don't worry too much about surprising him with new ideas; it's not your job to entertain him...

What I'm saying is, he most likely will be very glad to be used by you, for yourself. You're soon going on a weekend trip with someone who is "willing to do anything you tell him to", so close your eyes and envision what turns you on most. I'm sure he'll like that best.

Oh, and if you haven't yet, ask him too, of course. You can't always know his desires and maybe he'll give you a good idea or two... Let the guy spill his fantasies and smile when asked about yours, that should keep him on his toes.