I find most intriguing how you place the islands in many curves all around the two continents. It gives a certain thorny aspect to it, like a wild bush. Its a beautiful touch of creativity which gives much details not just to the landmass, but also to the ocean which breaks in so many seas.
I seldom find such talent in handmade map...
I also must point out the continuity of your style. Hills, mountains, forets, grass, waves, name it, they are all drawn ''harmonieusement'' I would say.
As for the colours be careful. I draw black and white as well, by hand. In my case, I was told by many not to add colours. Textures are often more than enough to create what you want, but if colours you must add, then I would suggest a pale gray-ish tone.