There are no official formal or semi formal nights on the 3 and 4 day Wonder cruises...Tritons Rest. & Palo are dressier than the others, but no formal night.
By all means feel free to "dress up" the night you are in Triton's and/or Palo...you will not be out of place and it's a great way to celebrate a honeymoon.
Like the idea about returning for a 7-day! Go for it!
BTW -- Been on 2 4-days and had a great time dressing up for our dining rotation in Triton's. I would also not hestitate to get decked out for Palo. And seeing hubby in a tux on our 7-day was wonderful!
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