Very nice job !
It's very neat, very precise !
I guess, you could add shadings and nuances, to make it look more realistic.
I mean, for example, nuances of green for the forests, and nuances of grey or brown for the mountains.
You could try to add waves in the sea
And overall, more shades to give relief, around rivers, on the sides of valleys, and so on.
On top of that, you could add clouds in some places
I don't know if that's good ideas or bad, it's just what I would try.
But I find your map really nice the way it is now : it has an "atlas" look that I love