Here are my observations. Keep in mind that I'm relatively new to this lightweight stuff myself.
12 ounces worth of stuff sacks seems like a lot….maybe use plastic baggies to keep organized. If you lighten your load, you shouldn't have a need to compress your gear to fit it in you Z-55. Especially if your trip is only a day and a half.
Your kitchen is heavy, primarily the 9 ounce cookpot and the 14 ounce fuel can. Lots of lighter options here.
I think 3 ounces of toilet paper is overkill for a day and a half for two people. Not much, but maybe you can save an ounce here?
Possibly ditch the packtowel, replace it with a bandana, or cut it in half and get by with a 2 ounce packtowel.
For a headlamp, I like to use the Photon Freedom with a hat clip. Not the best for night walking, but for around camp and in the tent it is plenty of light and only weighs half an ounce.
You could also lighten up on the pocket knife. A Victorinox Classic has a blade and scissors for under an ounce. Do you need all the additional gizmos?