i'm an affecte person myself. I dont have macula degeneration though but suffering from Rethinopathia pigmentosa, which results in nearly the same needs for computer work (black background with bright foreground, big fonts and such).
My experience with flatscreens are, that they are worse from me because new big flatscreens come with gazillion of pixels in resolution. Even if they are big in inches this high resolution degrades the visibility again by displaying even big fonts very tiny. Also, most LED flats have a native resolution (very big) and if you change it to a lower resolution you end up with a blurry display. So for me i stay with tube screens (17" at the moment). But they are difficult to purchase nowadays and they need a lot more of space on desk of course, but if you can grab one i'd recommend such one. They are up to 21" or so in the normal consumer market.
Bigger is not always the solution though. In my case, i need to go very close to the screen with my eyes to see good enough. And when the screen is too big, i cant see the edges of the screen without moving my head left and right (because of the seeing angle which is constrained for my eyes too). Keep that in mind when deciding for a monitor size.
For the cursor. I dont see the idea behind a BLACK cursor with BLACK background. That is strange. Well the same problem occurs when you have a program that uses bright background and have a white cursor. My solution here is, using a multicolor, color-cycling cursor. That one is big and i can spot it everywhere on the screen, nevertheless which background it is on, because the bright colors (Red, blue, yellow) are moving all the time. So i can find the cursor even if i'm not sure, where on the screen it is located at the moment. If your friend is interested, i'd gladly share my curor with him. Just ring my bell.
If you want to get more of my experiences with other utils for visually impaired or blind or exchange informations about programs that are usable (color customizable) and all the other stuff concerning low vision and computer, just contact me again. Or point your friend to me, he is very welcome.
Just 2ct. of a self affected...HTH