Hakodate-Nikko-Tokyo?

Helloes,
I will be making a train trip from Hakodate through Aomori to Tokyo. While in Tokyo I thought of making a sidetrip to Nikko but I thought maybe it would be a better idea to make a stopover at Nikko and stay over for one night or two and then do the rest of the journey to Tokyo.

Is this doable, what do you think?

Yes, it is doable. Just note that the shinkansen from Shin-Aomori to Tokyo does not stop at Utsunomiya. You should change to a Yamabiko shinkansen at Sendai and then to the JR Nikko Line at Utsunomiya.

Uji,
Thank you for pointing that out. I had missed they do not stop in Utsunomiya. Since my JR pass is on the last days of usage it would make it easier to make stopovers and so.

I thought of taking an alternative route to Tokyo after that, since there are apparently more direct routes. One goes to Shinjuku but partly using Tobu railways tracks the use of JR Pass maybe is not possible?

Or can I do like the railways from Nagoya to Ise-shi and pay a fee for usage?

Indeed, the JR/Tobu trains to Shinjuku are not fully covered. I never figured out what would be the supplement to pay, but I think it would be a relatively large amount.

Oh well, I better stick to the regular way then. Again, thank you for your help!