-Mouse is nice if you have to point at something or you don't know what to look from menus (help files too).
-Keyboard shortcuts are nice if you want to use a frequently used feature.
-Text commands are nice if you know what you are looking for but don't know a keyboard shortcut for it. Then you could just type in a command name or abbreviation of it. Ie. if align would be the only command starting with "al", it would be expanded to "align" automatically, and user could just hit enter then to invoke command. Easy to run any command without point and click all around.
