happy, I know that 2017 and newer Trolls had a frame redo and can take up to 3in tires. My wifes is a 2017 and they rejigged the area near the bb to widen it.
The whole rim width thing though may come into play in terms of how narrow you'd ever want to go, and I imagine the ECR comes with wider rims as is.

The trips that you and Tourist have done, or want to do, seem like a million miles away from out here in the east. They do look pretty darn cool though.