If it's an internal application which a number of people use all day everyday, keyboard shortcuts can increase productivity immensely.
It doesn't matter too much what they are, because advanced users will learn them regardless. The safest ones to use, however, are the arrow keys. Also, Ctrl + ⇧ + ANY LETTER are usually safe.
If it's an internal application, you also have the luxury (normally) of developing for a set browser/configuration/version. This can make it easier to map out key bindings also.
