If I select, say, Modern as the color scheme, the result is as below.
How do I change the default color of the (I think it is) Title text, so that when I create a new note, it will default to, say, black?
Document settings have Text color set to black, so I guess that is just for the note body text.
You’re likely running into an edge case due to dark vs light mode: Modern was, if I recall, designed for light mode.
The color you want to change is $NameColor, which you can adjust in the Maps pane of Document Settings. The pane above adjusts the text color and background.
Not every attribute is in the Map setting dialog. In this case, $NameColor is almost invariably left as the default of automatics (black, white or an orange-ish colour if not eough contrast using black/white.
If you look at Map Settings pop-over and the sub-pages to Maps, you will see that $NameColor is not listed. Therefore you need to set the value elsewhere. You can set $NameColor in one of two places:
The Document Inspector ‘system’ tab. This sets the value for the +whole document_ as with Doc Settings.
For the current note(s) using Text Inspector ‘title’ tab
No, as it relates to an older version of the app pre-v6 and which was replaced in 2014. In map view, he colour of the note icon. I don’t believe that attribute even does anything in v6+. The background color of the note title ($Name) in map view is $Color, i.e. the colour of the note icon on the map.