So this has been an interesting one for me and I was thinking about this not just in terms of a
Disney cruise but in general.
1. One way halls/stairs on the ships -> absolutely fine as long as I know how to get to my room
2. Designated hours that you can use your balcony (to prevent people on their balconies on either side of you, above or below you) -> I don't see how this would be enforceable so no comment
3. Mandatory vitamin D/zinc supplements -> absolutely fine already take and one less thing to pack
4. BMI limits -> again unenforceable. You can't ask someone for weight and height and people could just lie and then turn up. You just wouldn't be able to deal with the amount of negative implications including discrimination (Discrimination by the way is the unfair or prejudicial treatment of people and groups based on characteristics such as race, gender, age or sexual orientation these are just examples and therefore this would still be a form of discrimination - just because we currently don't think of weight/bmi as one doesn't mean legally it isn't). I can certainly see them saying you must be vaccinated but just can't see them saying anything relating to weight etc as it would open a whole can of worms and lawsuits.
5. Elevator use by exception only, with sign up times, etc. -> again how would they enforce this and also this is disability impacting so therefore you would end up again with a load of issues there. I think they might try and restrict elevators to those who require it for medical reasons and I completely understand that but again they wouldn't be able to enforce as how would you prove you needed it?
6. Quarantine times before and after embarkation -> absolutely fine but no idea how they would actually enforce. After you leave the ship they have no control over you so unless they insist you book flights with them and pre-post hotels then they couldn't control this. Also a lot of countries have their own quarantine rules so they could end up enforcing double quarantine and then would get complaints.
7. No daily cabin cleaning/turn down service -> depends on length of cruise but I could deal with this as long as you can request new towels etc just in case. I wouldn't mind on a short cruise (4-7 nights) but anything longer I feel would need something.
8. Sign-up times for shuffleboard, miniature golf, ping pong, or basketballs -> absolutely fine
9. No one on upper decks during breezy conditions, since germs could carry further, faster -> absolutely fine but not sure its required
10. Confinement to quarters during certain times of day -> so this really depends on the purpose. If for example they say no one around until after 7am or something due to increase cleaning protocol I could live with it. If it was everyone back to their cabins between 2-3pm or something like that I'm not sure
11. No childrens' clubs -> not an issue for me as no kids
12. Two meals per day, to accommodate more distanced dining with an option for an additional charge room service for a third meal -> Why would you be charged for the third meal? Room service is free so I feel this would never be added. They could say 2 meals and then room service for the third but I don't see how they could charge. You've paid for three meals. That said I wouldn't like this restriction but I could live with it if room service had no charge.
13. Lottery system for shows and movies with a guarantee of one show per passenger -> One show per cruise? I think this would make me rethink a Disney ship. Other cheaper cruise lines then I wouldn't mind so much but part of the extra cost of Disney is for the shows I feel
I don't have an issue with the mask wearing around the ship and don't have an issue with booking times for things like the pools etc in advance or even having to sign up to activities in advance.