I don't think there's a standard when it comes to installing the different
desktop environments. In general, you should quickly check what packages
start with the name of the desktop environment you want, and from there
you'll determine which are the meta packages you need to install.
You should read the descriptions of the different packages which names sound
like they are meta. Also, you should check what packages come with the
different meta packages.
For example, the package "xfce4" installs only the core components of the
Xfce desktop, and "xfce4-goodies" installs other components of the desktop,
which are good to have, but aren't essential. On the other hand, the package
"lxde-core" installs the core components of LXDE, while the package "lxde"
install addition components, along with "lxde-core".
Typical core components of a desktop environment usually are:
Session manager
Window manager
File manager
Desktop panel
Typical additional components usually are:
Plain-text editor
Terminal emulator
Archive manager
Image viewer
In my experience, installing several desktop environments may create a mess,
because then you find yourself with several programs for each job. Several
plain-text editor, several terminal emulators, several archive managers, and
so on.
