Yeah it annoys me that it's so slow, it feels heavy. I think I once saw an application that could make the dock appear SLOWER than normal, so it's possible that it could also make it faster. The tiny problem is I don't know what that application was...
I have a 15 inch screen so I just leave my dock always visible and make it small. I like to know what's running at a glance. I don't like Cmd+Tab because you can only go either left or right, you can't jump to one application right away without using the mouse. And using the mouse is stupid if you use Cmd+Tab since it's a keyboard command anyway, you might as well just use the Dock then!