[Tagging] Admin_level=2 for non-independent countries

[Joachim]

While editing capital=yes I came across capitals of non-independent
countries which have their national border tagged with admin_level=2
(I just did a browser site search in
https://osm.wno-edv-service.de/boundaries/).

Wikipedia was used to assemble the list
(https://en.wikipedia.org/wiki/List_of_national_capitals_in_alphabetical_order)

The countries fall into the categories:
- Realm of New Zealand (only Tokelau)
- British Overseas Territories with Bermudas, Gibraltar, Turks and
Caicos Islands and others
- Crown Dependencies with Isle of Man, Jersey and Guernsey (quite independent)
- Danish Realm with Greenland and Faroe Islands

The following are grouped below their respective states:
- French overseas departments and territories
- United States Territories
- Australian External Territories
- Kingdom of the Netherlands (Dutch Caribbean)

Question: Are there any improvements possible, e.g. creating some of
the constructs above and order the countries below?

Question: Should capital=yes mirror admin_level=2 or should
capital=yes be used for independent countries and capital=2 for the
other?

Regards Joachim