I don't think every story needs to end with a death, but sometimes, they do. The trick is knowing the difference.
S&L decided it wasn't going to be a story about
living, it was going to be a story about
life, which was really built into the premise of this being "Superman: The Later Years," where all the youthful, flashy stuff that's the typical comic-book storytelling phase was in the past, and we were seeing what these characters were like after they'd grown up, and were into midlife.
I didn't mind most of the final sequence, but "Double-exposed ghost stands up from their corpse" was already a cheesy cliche 50 years ago, so it pulled me out of the moment.
I'd say that and the callback to Luthor's ridiculous prison-domination episode (even the human chair!) were the big unforced errors of an otherwise-exemplary finale. It might've been hard to do with how sentimental the tone was, but I would've just moved to Clark's spirit watching his body and the boys in a cut.
I'm sure there were limits of time and structure, but I was really hoping to see both sets of parents, too. Both because the show's always been a little weird about how familiar the family is with Space-Dad and Space-Mom (which makes sense, because it's an action/adventure show and they're holograms who live in a crystal fortress who can provide exposition, so they're the ones we see), whereas I always want Clark to be a little more distant from them than he is with Earth-Dad and Earth-Mom. I feel like seeing the four of them all together would've put a nice button on that, plus the surrealism of two old people in flowing leather super-robes in the middle of a farmhouse in a heartwarming pose with two incredibly normal old people.
One thing I did wonder... With it being emphasized by Clark how the 'first time' he died was just darkness, it made think. Is it possible the interpretation is that Sam giving up a human heart to Clark and Clark then having a 'human life' may have actually given him a 'ticket' to an afterlife he wouldn't have gotten as a full-Kryptonian? Or is it just simply a "wasn't really his time after death 1"
I guess it just fell by the wayside after it was introduced (maybe it was supposed to just be a red herring so we'd think he might genuinely be permanently dead but still on the show?), but I was kind of assuming that Clark would've remembered the five minutes he spent being a hologram, given the other holograms seemed to be "live" up to when their originals died, so I figured the connection would go both ways while Clark's body was in suspended animation.
That would've admittedly killed the mood to bring it up, though.