I would not worry about the dress code as I see very little difference. Im on Oasis next, which I hear might be more dressy. RCL now also allows shorts at dininer in the MDR, no difference. I had people on my last RCL cruise in long pants and a shirt they bought in the port and braided hair on the women, hardly what I would call formal. Wear your formal if you want. Some will be dressed up, some not so much, just like on RCL.
Lock or unlock your suitcase, its just a suggestion. No difference again.
Carnival will automatically charge you the $10 pp per day tips. RCL supposedly doesnt unless you sign the form. My cruise roomie signed the form to pay my tips, and they charged me based on her signature??? RCL doesnt know what they are doing, they should just make it automatic. Envelopes to me are just a annoyance to tear up paper vouchers and stick in the envelopes on RCL. On Carnival if you remove the tips your name goes on a list, so those who wait on you will know it. Just pay them. If you want envelopes you can get extras at the pursers desk.
yes, now on Carnival, its been changed to be called Boarding Pass.