You are probably wrong about Grand Bahama which is set to open before the end of next year. Carnival will be putting another 90 million into HMC.
There is simply no reason for the leading cruise line, Carnival, to be on the bleeding edge. They tried with Paradise - a ship ahead of its time.
As for debt, Carnival Corp is the entity with debt, not Carnival, and it is getting paid down ahead of schedule. Orders for new ships are on hold which will allow for an even faster reduction in debt. Meanwhile Royal has several ships in the works which will only increase their massive debt and lead to lower prices for their cruises and lower profits.