If you are talking about putting lowering springs only on the front and keeping the OEM springs on the rear then that is def not recommended. The springs should remain a matched set.
If you are talking about using coil-overs and only dropping the front, that can be done but may have adverse affects on handling. Someone with more knowledge can chime in on the intricacies.
On a side note - I agree that the rear sits perfectly while the front could use a ~ 1" drop.