"And aluminum is "quicker" and more airy sounding to me."[/Q]
I hear it too. I liken it to the sound of a solid ASH body with no top. Neutral but airy. I don't have a steel bridge, but the description sounds plausible--similar to the difference between stainless and nickel frets. Steel rings loud and clean and tightly-coiled-spring-like: great for clang, snap and pop. Nickel and brass are softer and warmer. Aluminum is a stiff, light crystal--and that's what it sounds like.