Should I purchase a JR Pass?

Hi

I will travel to Japan 18 April - 6 May:
Apr 18 Tokyo (Narita) → Kawaguchiko
April 19 - 20 Kawaguchiko
April 21 Fujinomiya → Tokyo
April 22 Tokyo → Katsuta → Hirosaki
April 23 Hirosaki → Aomori
April 24 Aomori → Hakodate
April 25 Hakodate → Sapporo
April 26 Sapporo → Osaka
April 27 - 30 Osaka
May 1 Osaka → Kitakyushu → Fukuoka
May 2 - 3 Fukuoka
May 5 Fukuoka → Tokyo
May 6 Depart Tokyo (Narita)

Please advise whether is it worth getting a JR Pass and which pass would you recommend please.
I notice that sometimes travel by air is also cost effective (for instance, from Sapporo to Osaka via Chitose is quite cheap).

Arigato gozaimasu.