Get a Classic as a fob for your key ring, and an Alox Bantam for the other pocket (and for serious cutting and opening bottles and driving screws). The Bantam has negligible weight and bulk. Also, if you can do without the scissors, a Cadet alone might be perfect.
I almost never use scissors, even at home. A sharp blade can do most jobs for which scissors are normally used. Often people resort to scissors because they haven't experienced what a really sharp knife can do with limp materials such as paper, string, and cloth.