That is a great idea and, fortunately, that feature is already part of the
"new" Installer, version 3.0 which ships with System Software 6.0.4.
To invoke it, either hold down the Option key while launching the Installer, or
after launching the Installer, press Customize, then hold down the Option key.
Note that holding down the Option key changes the "Install" button to a
"Remove" button. Releasing the button key changes to button back to Install.