Got one pattern flight in the books with no plugins other than Gizmo.
Loaded up xEnviro as the first test subject as it was mentioned in this thread; setup a flight from KHYI to KFST, and made it to near 15k' before it crashed. So early results do point to xEnviro, which is disappointing as I have not encountered this problem with my other primary aircraft (IXEG 737, FF757v2, STMA PC-12). I'll try a few more flights with it installed and see if the results are the same and run through some of the other plugins.
Edit: Ticket filed with the xEnviro folks, but I'm not sure if it's all on their side or a shared issue.
GizmoLog.txt
Log.txt