>>> 1) Option or command to automatically go to the other end on exit.
>> 
>> It seems the conclusion was that it should not be an option. As for a 
>> command, there were objections against binding it to a key, but without 
>> a keybinding such command has little sense.
>
> I attach a patch which implements these two "options" in isearch-exit.
>

And of course my patch had an error ;-)