As a lifeguard you would know not to treat beyond your scope of training. As such, if you think you will need it, get more training!
Cell access and <1h to critical care negate a whole bunch of the necessity of a big kit (ie. what you have it likely enough)
Wilderness presents a lot of challenges and potentially a situation of prolonged care if your find yourself without access/communication.
If you realistic about your needs and your abilities, you can likely create a kit for yourself as you discussed. No one can ever have enough kit for every eventuality.
However access to communications for evac (cell/radio/sat/iridium etc- which are rentable if you are really out in the wild!) is crucial. Distance and time to primary care will dictate a lot of what you need to prep.
Minor stuff- a boo-boo kit is very helpful. A full blown trauma kit? unlikely to be carried and its of limited use if its an hour a way at camp.
I cannot say I agree with the advice above on TQ's, but the protocol should be direct digital pressure, bandage, bandage, TQ.
In remote situations your enemies are the "Trauma triad of death".. in short, you aren't likely to die directly of a broken leg, but hypovolemia and shock, can cascade into a high mortality outcome.
In short- things that will kill you, you will need access to additional care/resources so have a plan and communication. If you qualified/able to provide the critical interventions to stop deadly bleeds, stabilize fractures, deal with penetrating chest wounds etc, you increase survivability.
Comms is critical. We carry UV5R radios and have the police (Ontario Provincial Police) radio room and Coast Guard Search and Rescue freq's programmed.