We have been to Japan 3 times already (love JR pass), covering the main sites of Tokyo, Nara, Kyoto, Kanazawa, Takayama, Hiroshima, Shikoku etc ie basically everything south of Tokyo.
Apart from having visited Nikko we have never seen the regions north of tokyo - Tohuku or hokkaido regions so plan to do this in August.
Itinery Arrive NRT, fly to Sapporo.
5 Nights Sapporo and explore the Island. Start 14 day rail pass.
Then 3 Nights Aomori, exploring L Towada etc
Then 3 nights Sendai, exploring the coast etc
Then 2 nights Yamagata at a ryokan
Then 3 nights Tokyo end of railpass.

We prefer to base ourselves in fewer hotels and explore by rail etc (rather than 1 night here one night there), so could I ask the Board what are the must see's for us in Tohuko etc