I only use KDE, so I can't comment on Gnome etc.
Dragging a file into Konsole (KDE's terminal) gives a menu with the options "Copy here", "Link here" and "Paste location". Seems reasonable.
Dragging a hyperlink or image from Chromium gave the same options. "Copy" downloaded the file, although set a timestamp in 2106 for some reason. This doesn't work from Firefox.
Dragging selected text pastes it in.
"see ." opens the current directory in the file browser thing, "see thing.odt" opens LibreOffice, "see my.pdf", etc. "see http://example.org" doesn't work, although I can right-click the link to open it. (Naturally, "alias open=see" if you prefer that word.)
I set a custom shortcut for Konsole for "Super+C" etc (Windows/Cmd key), but I don't use it very often. I mostly select + middle click to paste, which is a Unix convention I miss on a Mac! The readline keys are nice, they seem to work about 80% of the time on a Mac, and I haven't found a way to get that working in Linux.
My "lots of little things" favours KDE. Properly maximizing a window, having a "keep above" button for any window, focus-follows-mouse, and the general feeling that the computer does what I ask in a boring way, not what it thinks I want in a stylish way.