To answer your other question, you'll never know the ship is sold out from the way it feels. They DESIGNED the ship to sail "sold out" so they have room for everyone to enjoy different activities without feeling crowded or herded. We sailed on the Magic May 1st and the sign at guest services said that "Captain Mickey says the ship is full so no upgrades were available".
Yes there were lots of people and some activities were more popular than others but it was nothing like the crowds at the parks on a busy day. We were able to do all the things we wanted without a problem. We were all adults so we weren't interested in the Mickey Pool or the Goofy family pool. Those can get crowded.
We toured the kids clubs a couple of times during the week and there was room for all the kids to participate easily. I believe embarcation night can get pretty busy in the clubs because lots of families check them out the first night.