I'm pretty 'meh' on the sea color as well - through this process I've found I'm horrible at picking colors, and nothing I've tried yet for the ocean has really grabbed me.

Good point on the mountains. I went and checked out the maps here:

http://www.shadedrelief.com/natural2.../download.html

The best comparison I can find on a map of Earth is that those mountains are about the size of the Himalayas and the Tibetan plateau, with the Kunlun and Qiling ranges, if one were to cut+paste that formation onto Africa.

I think if I were to keep that size, I need a more well-defined ridge on either the north or south side of the mountains to show where the plates are colliding.