I think the main purpose of these aircraft will be to compete and take back some of the market from Alaska. They've been increasing their direct service to the smaller airports in Hawaii, avoiding the major hubs. They do this in ETOPS certified 738s.

HAL can't compete with ASA using a 767 or A332, so I think the 321 NEO will probably be used just for that - direct thin, secondary-to-secondary Hawaii routes.

But as others have mentioned, I'm not sure the A321 is the best option. I know it is the NEO version, so we won't know until it gets closer to firming the design, but I don't think it will be able to do what the 738 does. ASA makes flap 25 takeoffs out of some of the tighter spots with very short runways - don't know if the 321 can pull that off, I believe it is a bit of a hog at the higher weights.

And as someone already mentioned, the NEO will have geared fans, which is a new technology that throws another very possible failure spot in the power plant department. I remember a stat that said the biggest failure contributor in a Cessna Caravan is the gearbox. I know it does not compare to a jet, but some of that does transfer over, especially for a new unproved design.

So I can't see ETOPS approval being that quick. Then again, after the whole 787 debacle, I'm not too impressed by the FAA's oversight.