Thanks for the writeup.
The problem with the hyperloop isn't the speed at which everything is going. It's the sudden stop when something goes wrong.
During the Bakken oil boom, BNSF spent a lot of Warren Buffet's money in Minnesota and North Dakota fixing some of the mistakes that BN's management made during their 80's extract-everything-possible-for-shareholders phase. Some of it was spent on re-installing double track on 10 miles of it just west of the Twin Cities that was pulled up in the early 80s. There was also a bad winter during that boom (2013?) that was hard on the heels of a bumper harvest. It swamped both BNSF and the CP (the two dominant rail carriers in the Dakotas), and they had an awful time recovering from it. There is more pipeline capacity in the area now, so there are a lot fewer oil trains going east on the River and St. Croix Subs.
The Empire Builder remains a critical service in the transportation-starved country of northern Montana. All the other land-based transport going east-west through Montana is focused on the I-90/94 corridor in southern Montana.
Also, I'd like to think a second Builder train set from the Twin Cities to Chicago, or an overnight sleeper service, would be a hit, but that's just me.
I'm going to be working in MnDOT's Rail office from mid-February to the end of May, which should be interesting.