So I looked it up briefly. It was going to be a "Where are They Now?" kind of book, which is what #54 essentially became. Originally, #54 was just going to be an extended battle and ending to the war, but KAA's contract got cancelled before she could finish it all up, so she just had to merge it all together.
I appreciate that KAA wasn't afraid to back down from completely shattering characters' lives, but I just think that the final chapter in #54 was a bad note to end on, just dragging it out slightly too long without adding anything relevant and creating an unnecessary cliffhanger. If you just ignore all that stuff with The One and just have them flying off to rescue Ax, then it's a great ending. I mean, naming the ship The Rachel is a great line to end the series on. It leaves things so open to imagination and interpretation. It's just Marco's final chapter that kills it for me. KAA said she was going for a sort of Lord of the Rings style ending, but LotR's ending wouldn't have worked if Sam was watching Frodo sail off into the sunset and a huge Kraken suddenly jumped out of the water and tore his ship apart.