We've never sailed Hawaii, only visited with land trips. Although we've enjoyed Maui, I agree Lahaina was just okay, I loved Kauai and Hubby loved Big Island, enough to return several times. We witnessed this explosion while have lunch in VNP. The left is our pic, taken with an iPhone from over a mile away. The earth literally shook. Very COOL experience and nothing that anyone could ever plan for.
So all that being said my best input for the OP is that any vacation wether be by land or sea will have many plusses & minuses, lots of variables at play. When it comes to price drops after final payment, you just need to let that go. Motto: You win some ~ You lose some, in the end it all comes out in the wash. IMO Celebrity still offers a great product, when looking at other comparable lines, they exceed in service, dining and overall ship design.
Cruising has changed, the traveler has changed and life as we know it has changed.
Enjoy Hawaii,
Patty