I love pixel perfect drawing… I mean I use it almost exclusively. Not to nitpick but it makes no sense to have the second color pixel perfect. Most of the time the second color becomes the value of the eraser. And when you erase using it. it is always a hassle because it always leaves artifacts behind. My suggestion is have a radio button that you can switch on or off that would allow you to use color zero as paint without pixel perfect drawing while at the same time using pixel perfect drawing on the other button. This would allow people to erase without artifacts while at the same time using pixel perfect drawing to draw with.