@firmagorilla I've been saved by my helmets a couple of times (brain injuries & abrasions). First time I was doored and got hit by a passing car. The second time I was cut off by another bike and I attempted to use my face as brakes down the road. I still have my right ear thanks to a 'Stackhat' (horrible looking helmet that is more like an ice hockey helmet than a bike helmet). This was before helmets were compulsory in New Zealand. I've only left for work once without my helmet and I got about 100m away and then felt odd (naked feeling) and realised what it was, so went back home.
I suspect that one HUGE difference between The Netherlands (and Denmark etc) and Australia, New Zealand and the US is that in AU/NZ/US car drivers do not give cyclists room and there are few dedicated cycle facilities. You're right about limbs too, and that's why I wear gloves. And safety glasses (tinted for day, clear for night) to stop the stones flicked up off the road removing an eye.
As for the commuter pack, nothing beats spare tubes. On anything over 30km I take two, for daily riding I take one.