It's an excellent idea, drawing helps me with my depression and suicidal thoughts, but it may not be a direct route to a better self esteem, but I may be wrong too. Give it a try for sure. Imagine a straight vertical line. On that line put a dot where you think your self esteem is. And if the dot goes up as you draw more then it is helping.

For example on my line my self esteem was below 0 when I started counseling sessions. Then it went up to 3, and the highest point on the line is 15, the middle number is 7, which is what Im aiming for, it supposed to be ideal. Too high is overestimation, too low is low self esteem.