JR Pass queries

Hi there,

Four of us (adults) are travelling to Japan 1st - 20th Oct 2023. Our broad itinerary is: Tokyo (leaving Tokyo on 6th October so activating JR Pass that day), Takayama, Kanazawa, Fukuoka, (then Nagasaki and Aso but we are hiring a car on Kyushu so won't be using trains beyond Fukuoka) then back to Fukuoka on 16th October and on to Kyoto and lastly to Tokyo on 19th October.

We are assuming 14 day JR Pass will be more economical than separate tickets especially as presumably we can buy at current prices? We are considering Green Pass too - not sure how much more that would be or what the advantages are other than space?

Is it possible to book seats online at all? Does it make any difference if you buy a JR Pass to pick up in Japan on this question?

Many thanks for your help!

Sophie