well, this is a very broad request - what menus?
in the 1D(s) panels, arrows are currently used mostly to change an item from a drop-down menu, and to increase/decrease numbers,
you can, however, use arrows to move through the names (not values on the right) in 1D(s) panels (when you click on them),
further, when you click an item name in a 1D(s) panel, followed by clicking the TAB button, it will highlight its respective value on the right side of the panel - so the preselection is made by the TAB key,
copy-pasting works on more levels, as well