How would this combination do?
Would the NuForce bring out the bass of the coppers?
Honestly the Coppers do not need to have their bass 'brought out', unless you are seriously into the low end.
As far as I know, the icon mobile is a little bright though and may actually serve to balance the sound of the MTPC. IME the coppers do respond well to a bit of power, so the setup may work well. The uDAC was great at driving mine so the mobile may just be the ticket, especially if you have use for the usb input function.
EDIT: Just saw on another thread that you do indeed want more bass with the coppers, and the FiiO E5 may be the way to go. It has a bass boost function and is really cheap so you arent really risking muck.