OK, so I have to retract much of what I stated at the outset of the thread. I uninstalled Krypton, deleted userdata folder, and even cleaned the registry. Did a clean install of Jarvis and guess what - it crashes too! Could have sworn this never happened before on Jarvis or other previous versions, but definitely happening now on both Jarvis (16.1) and Krypton (17.3).
So next I did a clean install of 17.3 in the same way - uninstalled Jarvis 16.1, deleted userdata, cleaned registry before installing Krypton 17.3. I then set up a few files in a local source folder and added to the video library. After several tests, here's what I can see so far:
1. It appears that bit-for-bit BD rips to MKV (using MakeMKV) do NOT crash Kodi no matter what I do. I can play with settings, skip forward/back, pause/play, whatever and it just keeps working. I even tried this over smb using file manager and it still plays without issue if the video source is a full BD rip.
2. Anything else is sketchy. Besides BD rips, I primarily have re-encoded/compressed MKVs (using Handbrake/MCEBuddy) and WTVs (recordings direct from WMC) as my source video in the library. I can reproduce the crash with either type of file if I play them long enough or fiddle around a while with settings, skip forward/back, pause/play, or some combination thereof. Sometimes crashes right away, other times after a few seconds to a few minutes, and sometimes not at all.
Here are the debug logs (made using local sources played through video node):
Successful playing of BD rip is here:
https://pastebin.com/3TRhMfjQ
Crashed playing of compressed MKV is here:
https://pastebin.com/hNr5wFKZ
Crashed playing of WTV is here:
https://pastebin.com/7xAsaMZq
I really appreciate everyone's efforts to help. I can't see what the heck is going on but it sure is frustrating. If anyone has any insight or suggestions, I'll gladly give it a try.