There is a world of file managers beyond GNOME's Nautilus and KDE's Dolphin. These are perfectly good file managers, but they're fairly heavyweight and drag in a ton of dependencies. Gentoo File Manager, Rox-filer, Xfe, and PCManFM are some excellent alternatives that are lightweight, powerful, very configurable, independent of any particular desktop environment, and well-maintained. All of them have complete graphical functionality, and also support keyboard shortcuts and command-line operations. If you're looking for something a little different, give these a try.