cool stuff. looking great, Flawedspirit

just a suggestion, but perhaps putting it into wilbur next to get realistic errosion and rivers?

Sifaus: try using a height gradient as a layer mask? I used one in one of my maps turned out nicely - here's a tutorial I just found that may help

for colours, perhaps work out what part of a planet your map is on? on the equator or near a pole will be a a starting point.