If it helps, my last crash was a "Failed to load Coherent DLL. Error code: 0x5". Me and two of my friends crashed at the exact same time, no report window, no "GW2 is not responding", straight to desktop. I believe it happened at Thunderhead peak during south meta.
I and one of my friends can't run DX11, I have 56 or so character slots, and my friend just crashes with "GW2 is not responding" whenever brandstorm is being rendered.
The other friend has DX11 enabled, and hasn't crashed other than the "straight to desktop no dialog box" crash before mentioned.