KBlairIf you put '-condebug' as a launch option you'll get a copy of your console output in your tf folder as 'console.log.' If you do that and post the contents, I'll be able to help you better.
As for random crashes, in my experience it's almost always something with hardware and more specifically, memory. Run Memtest86+ overnight and let me know if any errors show up.
I ran memtest for 5 hours with 4 passes and had 0 errors. I'll let you know what the console says if anything when I crash.
EDIT: From what I can see when I crash it doesn't say anything relevant in console.
"Rupee connected
gR| Mediarch killed raze soldjer with scattergun.
The_Salt killed Chumekin with tf_projectile_pipe_remote.
gR| Mediarch killed StateFromJakeFarm with scattergun." and then I crashed a few seconds after that.
Only thing I can think of is the way my medibeam is set up it spams the console with
"Attempt to set particle collection medicgun_beam_attrib_overheal_blue to invalid orientation matrix
Attempt to set particle collection medicgun_beam_blue_targeted to invalid orientation matrix"
alias secondary "slot2; medigun; +attack; r_drawviewmodel 0; viewmodel_fov 0
Maybe there is an error limit or something Idk