I just got off the phone with
DCL - they finally have some information on a post-cruise excursion to
Disneyland Paris. (I didn't see anything on the website.)
Disney is offering a three night hotel and length of stay (both parks/hopper) ticket package with ground transportation and an air option.
The price depends on the hotel. Newport Bay is $700/adult and Hotel New York is $770/adult. This includes ground transport from the Paris airport to DLP but not anything from the ship to the Paris airport.
They don't have price with air from Barcelona (and I assume ground from the ship to the Barcelona airport) is not yet available.
I don't know what the luggage allowance with that air option will be. I hope that they'd apply US rules. (Remembe that luggage allowances/charges in Europe are very different than luggage allowances in the US and on international flights. The second bag charge in Europe can easily be more than the ticket on low cost airlines.)