Right now, the Button Setup dialog box looks like this:
To associate a parameter with the button, it's necessary to (1) click on the scroll icon, (2) enter the parameter, then (3) OK your way back out. This is 2 unnecessary actions per button — #1 and #3. It should be possible to perform #2 (entering the parameter) right here in the Button Setup dialog.
I just completed making 20 copies of a button that'll perform a certain action (copying data in a particular field from one record to another), and the only difference between the 20 buttons is the name of the field affected, which I'm specifying by parameter. So this is 40 unnecessary actions associated with this one small task.