Scaling and elevation are looking good, but the mountain areas are really round. This is fine if (a) it's fantasy, who cares?, or (b) the world is more volcanic than tectonic (like Mars). If you want it to be more earthlike, you'll have more linear mountain ranges that happen as large plates collide with and move away from each other.

Of course, I'm only bringing this up because you said specifically that you were looking for realism; it honestly looks great as is. I like the color scheme and the style you've got going alot.