My basic rule is not to carry a tool or supply unless I know what to do with it. I, personally, would leave the spare spokes & spoke wrench at the beloved LBS. A broken spoke isn't necessarily a show-stopper for a short trip.
I was taught to never to anywhere without matches & a knife. They are light, and if you need either one, there is no good substitute.
I'd take one extra tube and a patch kit. Change out the tube (if necessary) and that evening, in the comfort of your hotel room, patch the other.
I'd take 2, maybe 3 total bike outfits - shirt, shorts, socks, bra. Pack each outfit in a plastic bag and off you go. Some hotels have washers and dryers (!) for guest use, use those if you can.
Off-the-bike loose clothing is vital. Just take something lightweight and loose.
You will forget something you need. You will also take things you don't need. Don't worry about it, but learn from your experience.
Take your camera. Don't forget to take pictures. Take a notebook and journal your day. You'll appreciate the record of what you've done some dreary January day.
Take a spirit of adventure and a sense of humor.
Give big space to the festive dog that make sport in the roadway. Avoid entanglement with your wheel spoke.
(Sign in Japan)
1978 Raleigh Gran Prix
2003 EZ Sport AX