I seem to have solved my problem and thought I'd post it here for other unlucky people suffering the same problems. (Modern Standby woes...)
So I've been having this random problem where my laptop would suddenly crash. Initially it'd auto-restart (so I turned that off)
What was happening was the laptop was going into a form of sleep mode. The SSD would not recover from sleep mode correctly so the BSOD, stick at 0% during the BSOD and couldn't write a dump file or store an event in the event viewer (can't do that if you can't talk to the storage device, right?)
Turns out these laptops come with an Intel 660p SSD. It also happens that the firmware has a massive bug in version 002C which was not easy to narrow down.
I've been having other sleep issues which I thought were down to the BIOS, but seem to be related to this very specific firmware issue. Top recommendation guys, UPDATE THE SSD FIRMWARE.