I am enrolled in a jeet kune do school, my sifu is a direct student of dan inosanto, who was a direct student of bruce lee; If you know bruce lee you definately should know JKD is wing chun based.
I actually kind of like the attitude of wing chun more than most other martial arts because it seems like it is more onslaught until the threat is gone versus being part of and intermixed with the chaos(in a situation with multiple attackers)
All of these people telling you BJJ for real life combat are either complete idiots or just to much of a fanboy of UFC to know what they are talking about.
In a real life situation the last place you want to be is fighting from the ground, you'd be better off doing like you said and just slipping away and running.
in terms of lethality, one defining line for the police to use deadly force is if they are up against a hard object, such as a brick wall or the ground, if they are being attacked while pressed against such an object they have the choice to respond with deadly force (I.E. beat you to death, or shoot you)
If you kick someone in the head, their legs/back/head/neck can all pivot backwards and absorb some of the force. also your skull has a certain bit of flexibility or give, even if it is unnoticable in terms of human senses.
But if you have your head against the wall or the ground your head has no where to go and the only absorbing force is that formentioned flexibility of the skull, which in itself can cause brain damage, so your brain is aborbing 99%, if not all of the force.
Especially in the situation where you mentioned "a trap" for your drugs or what have you, that would more than likely be set up by multiple offenders, so while you're on the ground dilly dallying around playing fag cuddle with one of the offenders appendages, another one has already run off with your supplies, and one or two more of them are busy stomping on your head while you hold the other one for comfort.
In a real life situation, standing and punching, kicking, trying to yank and pull away would be in my opinion more effective, and MUCH SAFER.
Wing Chun is a good choice my man, a lot of its moves teach you to knock down your opponent while keeping your balance and staying on your feet, which will open that window for you to escape.
The only really criticizing comments I have is that as I assume a paramedic or ambulance driver you are most likely in a confined space, and even sometimes encumbered with bags/carts/boxes/carrying a patient, and wing chun is not really as suited for confined spaces or having your hands full/encumbered.
For someone that is in a confined space or carrying stuff/wearing a uniform/accessories, etc; I would really suggest Krav Maga, it was developed in Isreal and is mostly used by the military/police personel including the isreali special forces, and is even part of the cirriculum I believe for many of the unarmed combat courses taught in USA's various branches of the military.
I hope this helps, or at least not TL;DR
INB4TLDR