It's hard for me to be sure because of the small size of the image, but it looks like the X-shaped range on the left-hand continent is just two crossing single ranges. You might 'roughen it up' a bit by making two or three smaller, parallel ranges for each, bumping into the larger ones here and there to create gorges/big valleys and a more natural-looking ripple-effect as if (I'm assuming) four plates meet there and continually churn up the land. As it is now, it just looks too neat.

In some other areas, particularly that ginormous area in the northern hemisphere on the right, it just doesn't seem natural to me that every square inch of land is mountainous; if you look at maps of Earth, even the most mountainous terrain doesn't take up millions of square miles. Not that that couldn't happen on your planet, but I think it'd wreak havoc with some of your weather systems.

I love love love the continent shapes though, and the colors you're using. Just wish the image was bigger so I could get a better look at it.