We can't really propose using dragging and dropping for moving modifiers without having something like this in my opinion.
Here I extended the existing handler for panels to include moving the current view of the region when you move close to the top or bottom.
Here it is working, with a small region just for easier demonstration and a better aspect ratio. It looks like it skips a few times in the video, that's just a low framerate.
{F8479680}
Both the speed and the scrolling zone size are easily adjustable at the top of the file. The speed is normalized for the number of updates, it's a true "per second" value.
This is a diff from D7462