pyqx is a multiplatform graphics editor developed in Python and PyQt. It focuses in Pixel Art, bringing a easy to use, user-friendly interface that you will adapt to in a matter of minutes. And if not, you can always change it!
pyqx is brought to you assuming that you will use a graphic tablet to draw. Don't worry if you don't have one, for the shortcuts and controls are well designed to be comfortable while using the mouse too. The most convenient way to use pyqx is by leaving one hand on the keyboard and using the other with the mouse/pen at every moment. You won't have to move your fingers around every time you want to change the drawing tool: that's already been thought about.