The 7 note scale you suggest (do re mi fa so la ti do) is comprised of different intervals (2 2 1 2 2 2 1) in the 12-fold equal tempered scale. There are infinite ways of exploring an octave in music, but unfortunately listener demand for such exploration is near infinitesimal.
don't you mean 11-fold? ... oh wait, they aren't even consistent
They sum to 12
actually they multiply, 12th root of 2, to the 12th