Well so far so good and as for working on maps that large you get used to it. I've only done maps that are at least 2000x2000 and the only trouble I've ever had was when I was doing a world map that was 10,000x20,000.
Your forests (really, it's only the northmost one on the eastern half of the continent) look very confined, and it's clear there is a shape you wanted for them to conform to. It stops my eye and forces me to hover over it because of how unorganic it looks when compared to the mountains.
I'd also say put in more hills because where you have them really enhances the progression from flat land to mountains.