There is a point of diminishing returnsÖtoo little weight and you may suffer the lack of some comfort items; too much weight and your body will be beat too much to enjoy your comfort items.
Iím still active duty and have done my share of rucking and duffle-shuffles, but I try to keep the weight down in my recreational packs. It does depend on your activities. Weíre actually doing a short three day backpack trip tomorrow; itís only about 4-5 miles in to the planned camp site and then some fishing, swimming, exploring and day hikes. Iím looking at around 40 to 45 poundsÖIím packing my favorite chair, fishing gear and a smaller day bag for essentials. Iím comfortable with 45 pounds, but if Iím creeping up to 60-65 pounds, I really try and scrutinize what Iím taking verse my planned activities; especially if that distance is more than 8 to 10 miles. Your knees are good now, but over 40, youíll pay the price for ground-pounding too much weight too often. I do pack along the extra weight of a couple of cans of Guinness for my evening relaxation drills
The good news is that my son is now 13 years old and will become my personal pack mule. I can still pack along some fun-tools/toys and comfort items at his expense Itís only fair, as our first family of four backpacking trip had me packing 100 poundsÖI have no desire to do that anymore!
Also, the less you take, the more you think and the more you can improvise. Typical ultra-lite hikers want to go long distances quickly; ultra-lite bushcrafters want to leverage off their primitive skills, and most just want a comfortable hike with a few comfort items where they can relax and enjoy the outdoors far enough away from civilization to have the peace of mind. It's all a balancing game with what you intend to do.