Did they get the GTF engines to stop blowing up yet? The first major ETOPS routes planned for the GTF-equipped 321NEO (CEPAC Hawaii - West Coast USA) are some of the thinnest-margin "just barely 180" ETOPS routes out there. Some very competent people putting that program together, but not a lot of room for error.
I'm sure that, just like the 787 with it's lading gear issues and battery fires in the beginning, the 321 NEO will be a wonderful ETOPS airplane after the debug phase is finished. In the meantime..... We shall see.