I found after not using SketchUp Web for a month, coming back to it, I was unsure of the keyboard shortcuts. It would sure be nice to see little hints in the tool-tips that display over the menu items on the left.
For example, when you move your mouse over the Arrow, it shows “Select” in a little tool-tip. It would be nice if it showed “Select (__)”, “Move (M)”, “Rotate (Q)”, etc.
I think that would greatly contribute to the ease of learning SketchUp Web as well.