So, my super stable load order that I've had for many months now decided to blow up upon entering the falkreath triangle of death region, specifically around bilegulch, and entering the WolfSkull cavern. No idea why they've decided to blow up now. But's it's always been an issue that reoccurs in my games. I fix it and it seems to come back every time.

Time to go through my +400 mods (~140 esp/esms) and see what's breaking this time.......

EDIT:
I seem to have fixed my Wolfskull Cave.
Anything that seems to modify my necromancer robe or warlock robe mesh seems to cause the crash.

For Bilegulch (Falkreath triangle of Death)

The worse part is that it seems to be something that is a randomly generated variant. (maybe something on the leveled lists?)
It'll take maybe 3 or 4 times running to bilegulch from moss mother cavern before I get a crash.

EDIT2:
Yup it seems the IPM weapon replacer series on the nexus conflicts somehow, and causes crashes around Bilegulch. I removed it and ran through maybe 8 different times and no crashes.