It would be easy to tell captains they can only go on approved courses, but in fact part of the attraction of cruising is the fact that ships take you places you wouldn't expect to go on a cruise ship.
I have been in ships that navigate through Norwegian Fjords with just a few feet to spare on either side. But the point is that all of these trips are authorized with proper safety precautions already taken.
Ships go up the Amazon and Mississippi - two rivers famous for changing courses all the time - but they usually have local pilots onboard.
It is also important to give captains some autonomy. I was just on a music cruise with outside entertainment. A rainstorm came up, so the captain deviated the course a great deal to stay out of the weather as much as possible. As i said - airline pilots also do the same all the time.
The problem comes from captains taking unauthorized deviations to known dangerous places. This should not be allowed and when discovered that captain should be fired or disciplined. Schettino had a reputation for cowboy maneuvers - not a good thing.
It should be feasible to establish some guidelines for deviations where an independent navigator has to sign off on it, and he must also be on the bridge along with the captain to make certain all decisions are good ones.
But I still have to say that if cruise ship safety was as bad as many people are now implying - wouldn't we have a much worse safety record in cruising than we do have - like as bad as the airlines and highways, for example?
also - about the air tanks. Once again, they would only help in very limited situations. The problem on Concordia was that too many people were still below and didn't come to the upper decks. That was most likely a language barrier. They were still below when the ship listed sharply. If a ship is sinking in deep water (far more likely than what happened) the pressure would kill people before they ran out of air.
Listen - there are MUCH smarter minds than ours working on this problem. They have a system now that was just challenged by a situation they hadn't put into the calculations (a listing ship where 1/2 the lifeboats were disabled). They will come up with something to fix this.
Furthermore - a lot of this is going to come down to simple human error - not a system failure.
If the captain had sent an immediate mayday, if the abandon ship had been sounded earlier, if a check of all cabins was done immediately after hitting the rocks to get everyone out of the lower decks, ...
This tragedy could have been avoided by people making different decisions, and they were NOT following protocol. I think it is a little too early to presume the system is broken - it may by limited, but not necessarily broken.