As for a successor, if Johnny Depp, Nathan Fillion, and Robert Niles all turn down the job, then James Rao is definitely available.
Plus, let us remember he won't be stepping down for another four years. That's quite awhile.
Is Charles Foster Kane available?
Personally, I think he has been doing pretty well and keeping the tradition alive. I am interested in seeing how his theme park expansions will go under him.
2015 is still ages away!