Nice to run into another drawing game! Very cute art and I like the moods of people reviewing it.
I ran into a couple points of player friction, like needing to wait until the timer ran out even if I finished the drawings early, and I didn't fully understand why I got scored low for some paintings. In addition I feel like there were too many options available in the drawing system which was a bit overwhelming on a time limit; I also didn't fully understand the paint fading mechanic (there wasn't much of a warning) and I also didn't understand I needed to complete all three drawings at first.
To make the drawing even smoother, you can look at Bresenham's line algorithm as a way to linearly interpolate between points when the mouse moves quickly.