Blade Runner 2049 is as much an homage to 1982's Blade Runner as it is a continuation of the story. This was clearly a work of love and respect, from the sound effects and visuals to the soundtrack and mood. Hell, casting a Dutch actor to play the replicant villain was no accident. Even the ending is a straight-up tribute. It shares the same music and a similar selfless sacrifice, only with snow instead of rain.
That said, 2049 doesn't boast the same potency. There's nothing that quite matches Batty's "Tears in Rain" monologue or the "meet your maker" exchange between he and Tyrell. How could it, though? Ridley's effort focuses on the ultimate existential, the question not even Monty Python could answer, i.e., why the fuck do we go through all this if it just disappears the moment we die?
Instead, 2049 sort of evolves into a modern day Pinocchio, but instead of a wooden doll with dreams of being real, it's an android wishing to be born. By the end, he does find his answer to that question and, within it, his purpose.
Overall, I'm very happy this film was made. It makes you think, it makes you feel. Outside of a few cheap laughs, the vast majority of movies released have little chance of accomplishing either.
As for runtime, I'd apply the adage of "it should be however long it can be as long as it is good." I don't think 2049 could have ended any other way, with K on those steps, in the snow, confused and heartbroken yet, somehow, at peace.
Hollywood considers it a modest flop because it didn't earn back triple its budget inside of half a year, but I consider it an artistic achievement. I adore that Villeneuve et al. dared to make it.