You are the first person i have seen who enjoys the difficulty. I think, except for a few parts, Pirate101 has been a not very challenging game, and I am glad to finally have an entire world be challenging. As for if Book 16 will be more challenging, I think they'll do what Wizard101 did with Polaris, where we had Khrysalis which was very challenging, followed by Polaris which was pretty easy. ( Khrysalis = Book 15 Polaris = Book 16)
I think initially, in the test realm, it was maybe a bit too tough. But I am fine with the current difficulty level. I have had to make some adjustment to tactics, but that helps keep things interesting. The crew tend to take forced naps far more frequently than they used to, but no permanent harm there.
All in all, I am quite pleased with the new chapter.
The only time the difficulty really got to me was at Lucci villa. I had real trouble there, but once I unlocked Contessa? I was set for the game. She really boosts your team, and I was able to solo everything afterwards save for the Clock Works and The Machine.