Which JR pass to purchase for my itinerary?

Hi, please advise which JR pass do I purchase for my trip? Is it better to purchase single JR pass ticket in Japan? My itinerary:

Fukuoka Airport to Hakata Station
Hakata Station to Daizaifu Station
Daizaifu Station to Tenjin Station
Hakata Station to Yufuin Station (vice versa)
Hakata Station to Shin-Osaka Station
Nippombashi Station/Shin-Osaka Station to Universal Studio (vice versa)
Nippombashi Station/Shin-Osaka Station to Mihara Station/Tadano-Umi Station
Tadano-Umi Station to Okayama Station
Okayama Station to Namba Station
Namba Station to Nippombashi Station
Shin-Osaka Station to Hiroshima Station/Miyajimaguchi Station
Miyajimaguchi Station to Hiroshima Station
Hiroshima Station to Shin-Osaka Station
Nippombashi Station to Nagai Station (vice versa)
Nippombashi Station to Kansai Airport

Hope to hear from you soon.

Thank you.