C and I have been watching original Star Trek episodes via Amazon Prime, and entirely fortuitously, we were just up to "City on the Edge of Forever." Watching it seemed an appropriate commemoration for Ellison.
I'm seeing all of these after a gap of many years, and I'm repeatedly struck by several different things: episodes where a famous bit of canon ("I'm a doctor, not an X!") shows up for the first time, scenes that look disturbing in retrospect (for example, James Kirk flirting with Miri, who is purported to be just entering puberty), episodes that don't really hold up when watched critically—and other episodes that are still effective. This was one of the last group. The script gives Kirk a serious and dramatic conflict; and, somewhat unusually, Shatner's acting lived up to it fairly well, particularly after we see Edith Keeler call him on his bullshit. His final line, "Let's get the hell out of here," was a believable reaction to what the character had just had to do.
I realize that Ellison wasn't happy with the rewriting of his script. But I think that the rewrite is dramatically effective and that it has to have gotten that effectiveness from Ellison coming up with a good central conflict, and one that followed logically from the sfnal premise, in the classic Wellsian style. So I think it still serves as a memorial to Ellison's virtues as a storyteller.