With regards to issues #6 and #7, I came to think of something @mastensg, I believe, mentioned when I was talking with him about saas-by-erik/timelog; validity of time zone names in the past and in the future.
Time zone names which reference a geographical location as Country/City might not be valid prior to the founding of the country and the inclusion of the city in said country.
Likewise, a Country/City pair might not be valid in the future. We can't know.
New Country/City pairs may be valid in the future even if they aren't today.
With regards to issues #6 and #7, I came to think of something @mastensg, I believe, mentioned when I was talking with him about saas-by-erik/timelog; validity of time zone names in the past and in the future.