Hey, first of all i think you need a really high quality image if you want to save all the detail. I tried to make the image completely in black and white and there are some tiny little pixels around the edges that you don’t want unless you clean them up manually. I downloaded a 4k world map from google and what i did in PS was:
apply adjustment layer (AL – from now on) B/W
merge down
apply curves adjustment with 4 points with input/output: 0/0,9/2,13/255,255/255
Now I have very good looking B/W image but because of the high res there are a lot of tiny dots that you can erase if you want to and apply invert AL. That way you can select just the continents and the desired detail in any color scheme you want.
Once you get the detail you want you are free to use it in AI and import it like high res .jpeg. On Image Trace settings (Window/ Image Trace)I used B/W mode, Threshold: 181 and in Advanced section: Paths- 100%, Corners- 100%, Noise- 100%, Method- Abutting, Create- Fills and Options- Ignore White.
That is the way I managed to trace the image pretty well. Is not perfect off course but I think it will work good for what you want to do. From here on you just have to make the dots for the effect you are searching for, that I imagine you know how to.
Cheers. Hope helped you. If you want I can send you the .ai ready traced.
