If I could apply constraints via assigned hotkeys, my work speed in sketch mode would double. Every line that I draw is followed by dragging my cursor over to the sketch palette, looking for the appropriate constraint, and then drawing the next line. (this is not including the times in which you click the wrong constraint on accident and have to fix it.)
If you have a sketch with 20 lines, that's many times that you have to drag the cursor over and apply the constraint. It may not seem like much at first, but as more and more lines are drawn that amount of time really adds up.
I am aware that you can first click a constraint such as "equal" and then click on multiple lines, but that often requires the person to plan ahead, which realistically is not always the case.
Another suggestion instead of hotkeys would be to assign the common constraints that I use to the right-click-menu feature. for example, "right click, then drag to choose a constraint on the menu".
Thanks!