I love Aseprite and have used it for a long time, but one feature a lot of illustration programs have that Aseprite doesn’t is the ability to flip the view horizontally.
This is separate from flipping the canvas horizontally, since that action affects undo history, and changes the image preview (whereas flipping just the view horizontally should do neither of these).
It’s a very useful feature for me because it lets me draw without physical and proportional biases from seeing my artwork only in one direction. I currently map a button to flip the canvas horizontally, since I do it so often, but would be great if a feature existed that excludes the two characteristics I mentioned above.