If you would remotely be interesed in trying Scuba diving.... go to the Coki Beach dive club and try it. We did (we are not scuba divers) and it was one of the highlights of the cruise...
The ice show is very good... and the parades are very fun. All of the entertainment is top quality and I am glad that we saw all of the shows.
As far as dressing up goes. I think that from now on, I may rent a tux to wear on formal evenings. I never thought that I would want to do that, but I do think that it would be nice to do. Everybody is soooo dressed up that it makes you want to wear something very nice. You would not feel out of place if you didnt dress up, but you kinda want to.
We just got back off of the Explorer a few weeks ago and loved every minute of it.
E-mail me if you have any questions...