Hi there!

I generally like the rivers and forests, but I'm not a big fan of the mountain ranges and the coastline. Mountains don't just appear out of nowhere, they're the highest points of a ridge that was created by tectonic activity. The land around the range is generally raised as well. Imagine contour lines falling away from the highest peaks. Since a coastline is nothing more than a contour line indicating an elevation of zero, it should be affected by the mountain ranges as well.
In short: mountain ranges NEVER end perpendicular to a coast. They either peter out before reaching the coast, or force the coast to jut outwards (and probably both). Take the Ural mountain range for example: it seems to end at right angles with the coast, but in reality it swings east and then west, and only dips under the waves for a short while before continuing on in the Novaya Zemlya island chain. Mountain ranges never just stop at the coast, as if the coastline defines the mountains. It's the other way around, of course.

Another remark I have about your coastline: compared to the relative complexity of your other features (the rivers in particular), the coastline looks very dull and straight. I'm sure you can come up with a more interesting, jagged coastline that doesn't deviate too much from your general lay-out. There are fantastic examples here on the guild, just check out the Finished section for example!

You could use a redraw of the coastline to take care of both problems. It shouldn't take too much of your time, and the end result would be both far more beautiful AND more realistic