Looks decent. If the map is super huge you might try cutting it into sections and working on the sections and then stitching those back together for the final map. If I may, I'll give a few suggestions for the mountains. They need another layer of noise to liven them up a bit. Try looking at RobA's tutorial here. Also try adding a mask with a slight blur to the mountains to soften your transition between terrain types. Lastly you might want to add a coloring layer to change the mountain color slightly so that it matches the background terrain (ie greener in the temperate areas, tan/brown in the deserts, white in the arctic). Good start to your map, keep at it.