Welcome to the site.
Your map looks pretty good to me. I don't know how you're going to digitize it so I took the liberty of expanding the central image to 5000 px across and 300 dpi.
I think I missed two islands in the upper north west.
This is the sort of thing I'd like to start with so I hope its useful. Its already a better world map than some I've seen .
Have some rep!