Oh gosh, the hotel accommodations are absolutely 5-star. I liked the hotel in London better than the one in Paris, but it was just personal preference. Some people lucked into a room at the Paris hotel with views of the Eiffel Tower. I only had a view of the street next to our hotel, which was okay, but not as good as seeing the Tower sparkle at night. The London hotel was just a bit newer-feeling and really fancy. When you get into the bathroom there, you'll see a dial on the wall. Took me a while to figure it out, but it's a volume control so you can listen to what's on the TV (or the radio stations on the TV) while you're in there. That was cool! The London hotel (The Chancery Court) was originally the Pearl Assurance Company offices (hence the name of the Pearl restaurant on-site). It's only 1/2 a block from the Holborn tube station. Lots of marble and dark wood throughout. Very, very nice!
The hotel in Paris, the Westin Paris, is a little older, but still 5 star. The turndown service was unreliable, but that really didn't matter much to me. It was a little weird that, instead of 1 king bed, I had two doubles pushed together. Again, it didn't matter much to me. One of the beds was directly under the chandelier in the room (which some other rooms didn't have), so I slept in the other bed. Just couldn't handle the thought of that big thing hanging over me at night. The room has nice big French doors, instead of a window, so you can open them up when you're in the room and it feels very nice and Parisian. I sat at the writing desk, eating white chocolate from the shop around the corner (Port Royal chocolate - very good), with the breeze blowing in through the open French doors. I felt so European!
One important thing to note about the rooms in both cities - the tubs/showers are much higher than those in the U.S. Don't know why, but they are. Some people didn't think about it when getting out of the shower the first day and ended up falling to the floor. No one was injured, but they could easily have been. I did have to hop a bit the first time, to keep my balance. It's just a very long drop from the tub floor to the bathroom floor. Keep that in mind and you'll be fine.
I think your plans for the Star Wars exhibit are a great idea! The idea of that exhibit was bantered about among our group. I don't think anyone actually ended up going, but it sounds like it would be really cool. Not sure where you could do the hot air balloon. I took the Metro to the Maritime Museum at the Trocadero, which has superb views of the Eiffel Tower across the river. Then, took the metro back to the Arc d'Triomphe to meet up with some other travelers. We then walked down the Champs Elysee, back to the hotel. Was a nice afternoon. We all took a little rest, then met up again to find a place for dinner. We found a little Italian place, called Pasta PaPa, near the Opera House. Family style dining, great food and good prices. If you don't mind eating Italian while you're in Paris, it's a great option.
Besides the backpack, I wish I could tell you all the other little things that made the trip so special, so "Disney", but I'd be giving away so much that was a surprise. I think the surprise factor was important in making everything feel special. I don't want to ruin it for you.
After visiting DLR, I think the Disneyland Hotel looks like the nicest of all and it is, of course, the most conveniently located to everything. I think you'll enjoy staying there. I'd just never be able to afford it, that's why I'd pick Newport Bay next time. New York looks pretty nice, too.
I've heard that Adventures by Disney might add additional destinations over the next few years. I certainly hope so. I'd take another trip with them in a heartbeat. I'd love it if they had a trip to New York city. And, of course, I think they should do a Pirates of the Caribbean trip to Jamaica, Bahamas and St Vincent/Grenadines. That would be the ultimate!