That should certainly be feasable by reprogramming the IPAC2.
One other option you have within the winIPAC software is to program a SHIFT funtion for each input on the board. This would allow you to have all admin buttons opperate as a shifted function of another standard input. For example, you could set "TAB" to shifted P1 SW1, "ESCAPE" set to shifted P1 SW2 and "ENTER" set to shifted P1 SW3. You can basically asign any key to any input or shifted input. This lets you keep a clean CP without cluttering it up with admin buttons.
By default, P1 Start is setup as the shift button. If you hold this down to enable the SHIFT feature, and press another key, for example, P1 SW1, you can have the IPAC send the programmed shifted keyboard output (eg TAB) rather than the non-shifted default output of L.Ctrl
Of course, you can always have dedicated admin buttons if you prefer, or a mix of both
Hope this helps
Edit: Just re-read your post "not a fan of shift inputs"