In 1940,segregation of blacks and whites was still in the norm.
Between freedom and safety, safety is more important. safety is more important because you can be free and safe. safety keeps you alive while freedom has endless possibilities. if you are completely free you may also be reckless; however, if your main priority is safety, that can assure a safer life without issue.
Aslan was there first in the area of the Stone Table, and later he moves to another place for the White Witch to use this area.
Writing a Postcard would most likely not be there ^^
It looked great :) hope this helped