The best solution I found is a combination of previous answers:

a) Display Settings -> "Pointer Outline Color" and set it to black b) press the 'option' key to convert the text cursor to a cross

Just doing a) doesn't affect the text cursor, it still has the white border and is remains as hard to see. But the setting change does affect the 'cross' that appears when you press the 'option' key, it becomes much more visible and easy to locate.