I don't think many medics can accept that intubation, especially in cardiac arrest, is really not a lifesaving measure and in many cases causes more harm. It detracts from high quality chest compressions, defibrillation, and things that we know improves survival. The majority of them haven't really been trained well at 2 handed BVM technique (the number of them that walk in with one handed BVM where the mask is basically not even making contact with the patients face is mind boggling). They also should be taught that LMAs are more than sufficient for the majority of cardiac arrest patients provided they are registering end tidal CO2 and the airway isn't floridly contaminated (I would stress to them that in the prehospital setting end tidal CO2 is absolutely a vital sign and just as important as the others, especially when it comes to airway). It goes back to the point made earlier that good BLS care is really the most important thing.
Also stop wasting time on scene with sick TRAUMA patients. These folks don't need an IV. They don't need an EKG, or blood sugar. They rarely in my experience need an airway. If you are going to make an intervention on a trauma patient in the field, it needs to be a quick and life saving intervention i.e. needle decompression, surgical airway, something of the like. Otherwise, get them to a surgeon.
For medically sick patients, they actually should be spending more time on scene. The number of cases I have QA'd where the patient was moved while being extremely unstable and ended up arresting during transport would make the general public really queasy. It's better to take a hypotensive patient or a hypoxic patient, and correct things on scene to the best of your ability with fluids, pressors (if in protocol), NIPPV, prior to moving the patient. When they move these patients and they are unstable, most of the time it's never even recognized when transporting them down the stairs or the elevator that they ended up arresting. Could have been avoided the vast majority of the time if they had stabilized and not freaked out.
They need to understand components of the history that are absolutely CRITICAL. ED physicians don't care about the allergies, or the fact that the patient is on atorvastatin. They care about the last known normal for the stroke patient, or whether they took their Eliquis this morning. When you pick up a patient from a nursing home, try to get as much information as you can, bring their meds etc, it makes an enormous difference to the ED team. For god sake, if the patient is DNR, bring the paper work from the SNF.
I also have given lots of lectures to medics about creation of a differential diagnosis, cognitive overload, resilience, breaking bad news, coping with stress/PTSD etc. They have been pretty well received. EMS providers in my opinion have some of the highest amounts of workplace stress compared to any profession in the workforce. Despite the snafus, and the critcisms I've highlighted above, they play an absolutely paramount role in the healthcare system today. You should communicate that to them.
I've done medical direction for some not so good fire based services, as well as for some really cutting edge ones. The vast majority of medics I've worked with are outstanding and willing to learn. As a medical student and future physician, you can also make a big difference and have an influence on them in a positive way.
Good luck.
