"Nice thing about day trips is it's not so tough to add in luxury items or weight. You're not carrying two or five days of food and/or water. I might suggest, though, however convenient, I would maybe rethink the two knives and two lights. Redundancy has its place, but you are not really likely to even need the first light on a day hike, and the grip-tillian will likely open a granola bar as well as a leatherman. It will also help you make a splint or lean-to much better. Just my $0.02. The extra weight of a headlamp and leatherman might e with it from a training perspective if nothing else."
The redundant tools and lights are part of my multi-day kit too. I keep all the small items in a one liter stuff sack that is easily transferred from day pack to multi-day kit. If that stuff sack is in my pack, I know I have all the critical goodies without going through a checklist. Same with my hygiene kit.
I do go out out solo a lot and this stuff is my insurance policy. Indeed, I carry more than the iconic SUL single edge razor blade and Photon light. I am quite conscious of the choice and comfortable with it. I carry a pocket knife plus SAK Classic and a AAA flashlight as part of my every day carry, so this bit is like my normal pocket load and I do like my toys. As it is, the flashlight is 1.8oz and the Leatherman adds 1.6oz. Seeing that the pair are roughly 1/1000 of my body weight, I think can handle it :)
My lighting strategy is to have two lights that both use a single AA battery. That prevents all the juggling with trying to replace three AAA batteries and carrying spares. I can swap the AA between lights if needed, plus the spare. With a single AA battery, it is possible to change a battery in complete darkness, which would be entertaining with three AAA's and getting the polarity right, let alone dropping one. I considered standardizing on single AAA battery lights but I liked performance/weight/cost of the AA models.
I totally agree about day hikes having a training aspect and the tendency for toys to creep in. Definitely the time I would haul an SLR and tripod. I see that need to add a camera to my list.