I pared my kit down to things I can handle- so lacerations, blisters, sprains, headaches, allergies. So I've got analgesics, allergy pills, my Rx meds, assorted bandaids, superglue, a Quikclot sponge, moleskin, Newskin, antibiotic ointment, a burn patch, duct tape, tweezers, nail clippers, a needle, and a SAM splint. My kit is stored in a 1 qt ziploc with room to spare (except for the SAM splint, which doesn't fit and I keep in a separate pocket).
Carrying gear to treat injuries that will require an evac doesn't make sense to me, so I don't. If someone has a major injury and isn't ambulatory, I will do what I can to keep them comfortable and from going into shock, but I'm not going to try and set a compound fracture or do any minor surgery. I have no medical training. Those are the instances where we'd push the button on the PLB.