Yes. These are exactly the things I am concerned about.
They are not that great dealing with an international audience. For example you can book
DCL in Euros (looking at the website from a European URL will default you to that), but then in my cruise group for the upcoming Med cruise several people have reported that they ran into (minor) issues with changes etc. because of the different currencies.
I hope DCL will succeed and Disney has proven in the past that they can adjust. But I am not sure it will be a definite long term success story.