It’s not what you want, but it might work for you. On the tool setting bar(The second line of the header) there is an offset dropdown button. You can right click on it and assign a hotkey. I used F5 since I know that F5-F8 are free. This brings the whole falloff section to the mouse cursor, but you can quickly see what it’s set too and change it if you want then just move the mouse cursor out of the box and get back to work. The only other option I can see is to create an addon/extension that will do it.
