I totally agree with personal traits but to me those mates seem inapropriate for the time period and for the type of the game (but it's just my opinion).
I appriciate that you mentioned loyalty of admirals, that could be an interesting feature (admirals might dissagree with you about the direction of research or your political decisions etc. and that might influence their loyalty to you)
And you wrote about dying because of natural causes, I think that admirals might be rather retired when they reach some age.