I'm pretty sure I encountered "City on the Edge of Forever" through James Blish's short story adaptation before I saw the actual episode cough cough years ago, because Edith's speech as televised:
One day soon... man is going to be able to harness incredible energies, maybe even the atom. Energies that could ultimately hurl us to other worlds in... in some sort of spaceship.
has always struck me as being incredibly blunt in comparison to what appeared in the short story version. Blish didn't work off the final shooting scripts but earlier revisions, so I assume Edith's "astronauts on some sort of... star trek"-like predictions must have been inserted by Roddenberry or maybe Fontana.
While some of the poetry and elegance may have been taken out of Ellison's script (along with other, more justifiable, changes), there's no denying that "City" is an absolute classic, and one of the few instances of Trek doing romance well.