Yes. When I say paint by hand I mean using the brush like an artist would paint on a canvas. Just plop some color down with a very low opacity and if you need more color then keep plopping more color down until it builds up to the point where you want it. I don't use a pencil for this since it has a hard edge while the brush has a soft edge. As for median color, well - yes and no. I change color a lot; I don't just stick with green for forests, white for snow, brown for mountains, and tan for deserts. I'll use a lot of different greens for a forest and mix in other colors for variation like tan, red, orange, black, blue, etc. With a low opacity the colors pretty much blend themself and, at least in photoshop, I can change the blend modes and things will change/blend in different ways. Say like I am using a light green and have the blend mode set to multiply, if I keep painting green over green then the multiply will make each successive brush stroke darker than the last. Now say I switch to a red and change the blend to screen, then each stroke will get lighter and browner since red and green are opposite. If I switch to overlay instead of screen then each stroke will just get browner but not lighter.