@OP
I don't like the idea of this change. Maybe implement something along these lines just for officers, but adding this additional frustration just for keeping the ship crewed does not sound like an improvement in game play experience.
What needs to be kept in perspective is that this is a game and first and foremost needs to be fun to play. While realism is an enticing aspect of gameplay, there is point at which it takes away from gameplay rather than adding to it. I feel like this feature will cross that line.
Realistically a naval battle took hours and sometimes days, even between just 2 ships. This game already has an 1 1/2 hour battle timer, which is quite long for a game. Would making the battle take 1-2 days of real life time be realistic? No doubt lol, in fact some extreme enthusiasts would love that. However that would make this game unplayable for most people, both from an aspect of enjoyment and shear time restraints.
I could go on and on with examples, but my point is if we take the realism too far it stops making the game fun, and starts making it dull and work-like. I don't see how the proposed change will do anything for this game, except make it more limiting than it already is. By that I mean it is already a game that most people can't or won't play because of the amount of time it takes to really do much of anything. Changes that take that even further will not improve this game in my opinion.
That's my 2 cents, make of it what you will.