You can do yourself a favor on the math alone. That 1.5 liter of fluid should be just over 3 pounds, not 4.8
And you can do even better than that. There is frequent water all the way up to Trail Camp. I only carry water above there. So there is 4.8 lbs you can take right off the top.
Also, is that a MINUS 20 bag? Way too much. You can lighten up there.
On the other hand, 750 ml of water for the day pack is way to little. 3 liters from TC to summit and back is considered prudent.
You can knock off significant total weight, but plan on a little heavier load for the summit.
