Congratulations!!!
I do not think I am a fan on having this type of artwork on the decks. I do not see the point as if I want to see elaborate sculptures, I would go to a museum.
I (and my family) am with you 100% on this one! We have been to a few Captain's Cocktail parties and none of them had a dress code. My husband and son always show up wearing nice shorts and a collared shirt which is always their evening attire. And when we were on the Epic this past March, the Captain spent a lot of time talking to my husband and daughter, so I do not think he was offended by his attire. So much time, he actually told my daughter (a Mechanical Engineer for a power plant) that he was going to have the Chief Engineer contact her for a private tour--which he did. Now if we saw a dress code on our invitation, we would not have gone and then my daughter (and husband) would not have gotten a private tour by the Chief Engineer.