The brush engine in Photoshop is one of the most robust I've ever encountered. The ability to customize brushes down to the finest detail, or to import and create my own, gives me an incredible amount of creative flexibility. I can simulate a wide variety of traditional media effects, which is something that other digital design tools often fall short on.
Layer management in Photoshop is also exceptional. With blending modes, layer styles, and adjustment layers, I have endless possibilities to manipulate and tweak my illustrations. It enables me to experiment without the fear of making irreversible changes.
