I have the Raspberry Pi 2 B setup with a touch screen monitor attached to the GPIO and my wacom drawing tablet (small) attached with USB. I have my GIMP settings setup so it hides everything. I just need to go into fullscreen and the painting covers the whole screen. I hide the taskbar and just use right click on the tablet to get it back. This is much better use of the screen. Grayscale and Colour tonal layers are posible but it's easier to just do the red line layer.