Japan Rail Pass - worth it?

I’m travelling to Japan in mid April to mid May and want to know if the JR Pass would be worth it. We will be there for 30 days but we figure if we get a pass it would be for part of the trip. We are kind of expecting this itinerary at least for part of trip.

Tokyo - 4 days Kanazawa - 3 days Odawara - 1 day Osaka - 2 days Kyoto - 4 days (Golden Week) Hiroshima - 2 days Fukuoka - 2 days Nagasaki - 2 days

Honestly open to suggestions as for other stops as this itinerary doesn’t cover 30 days. Is it worth it to go to Kagoshima or Kochi area?