Re: spaceIndex macro shows only pages created via REST API
I am not sure about this, but AFAIR the spaceindex macro is now (7.2+)
AFAIR, it only handles terminal documents in the provided space. Most
likely, using REST, you create only terminal documents so that is why you
believe it is connected to REST, but it`s not. Also, the "Create a new
page" button probably creates by default a non-terminal (a.k.a. Nested)
Page inside the provided space, so the macro will not show it.
The documentTree macro  should be used instead which is NestedPages
friendly and should properly display all your pages (terminal or
non-terminal) for the given root.