Welcome to the Guild Suffer! You've got a wise friend; it never hurts to seek a bit of C&C, especially from a community with as much collective experience as this one has. OK here are my thoughts: the general land masses look fine, and the hills and mountains look good as well. The one element that look problematic to me are the trees. Not only are the trees HUGE given the scale of the map, they also have these odd little white spaces between them that just doesn't look good. There are tons of other trees/forests textures out there on the web. In fact, I think there is a sticky in the Mapping Elements section that has a lot of other trees/forests textures as well, in case you wish to try a different one. You may also wish to vary the color of the land a bit to indicate more arid terrain and/or other climate regions. I see that you've done a little of this already, but you may wish to do a bit more. Also, try adding a Gaussian Blur of around 25-35px to these new layers of color, to help them blend in a bit better. Otherwise, not bad.

Cheers,
-Arsheesh