What works out cheaper:

Return NEX ticket & SUICA card for local journeys around Tokyo - as far as Ibaraki airport & the Atsugi area + 1 way Shinkansen ticket from Tokyo to Osaka

or a 2 week JR Rail Pass.

I'm planning to make the return journey from Osaka to Tokyo on the brokendreamsliner if it gets fixed by the time I visit Japan in October.