There are certain practical considerations when you're an artist..... least of which, where you work. I would love to meet an engineer who could build for me the perfect ergonomic drawing board and chair, maybe something gyroscopic so that it didn't matter which way you had to lean or tilt, you were always perfectly balanced, and the board could be tilted to the perfect angle and height, so that you could always reach the edges of the board without turning yourself into a pretzel....