To make an A321 with better range one/both of two things would need to happen so far as I can tell: more fuel capacity or more efficient engines, with the A3xxNeo pursuing the latter, obviously. I'm just skeptical that a modern advanced engine would be able to make any significant gains in range to easily fly PHX-Hawaii or East USA to Western Europe. But I'm no engineer, so what do I know?

Curiously, and referencing Wikipedia, so take it for what its worth, but it claims a max range of 3000nm for the A321, and airnav.com claims a flying distance for PHX to HNL of about 2500nm. If these figures are correct, then is the issue related to ETOPS requirements that prohibits A321s from making this trip? I suppose eastbound fuel requirements would also be taxing.

As for the 757, I wish there were more flying. It is probably my #1 favorite airliner. Sleek, powerful, capable; and given it still being immensely sought after by airlines around the world, it seems that I'm not the only person who feels this way.