What inspired this wish list request? I use another program where there is an option to have a vertical line on the x axis and all the values for the lines/curves that it goes though the values show along the line. This is really useful for seeing the values of multiple Y's at a x axis value point.
What is the improvement you would like to see?
Here is an example of what it looks like, I can see what the values are for all the curve at the same time. The value boxes are stacked in the order that the lines are vertically.
Why is this idea important? This makes understanding curve data a lot easier that having to move the cross hair tool up and down and try and remember the values or write them down.