You will love the Serenade of the Seas. Perfect ship for the Panama Canal cruise. In answer to your question about being seated at a large or smaller table... I think a table for 8 or ten would work best. Most people do dress up on formal night. I would guess about 90%. We always try to book an aft cabin. The reason being the balcony is much larger. Our second choice is a cabin on the hump. Here is a picture of our deck 8 aft cabin on the Jewel of the Seas, which is also a Radiance class ship. This should give you a good idea of what I'm talking about... CLICK HERE
Hope this helps...