The majority of places you will stay have one right in the room. Otherwise, ask at the front desk.
2. Expensive jewelry including watches
You are just asking for trouble otherwise. The less you are noticed, the better.
Borrow one at the hotel.
4. Extra credit cards and store cards
One back-up is enough along with your medical cards.
5. Baseball cap
Come on. Take it off when you come inside. Better yet, leave it at home. Locals will know that you are a tourist anyhow.
A safe rule of thumb: if you think you might need it, you won’t. Worst case, you can buy it there. Then you’ll have something new with a story attached, and what’s better than that?