In addition to Brightline, the other close relative of these trainsets appears to be the Austria/Czech Railjet (
https://en.wikipedia.org/wiki/Railjet). Railjet is another Siemens product with Comfort Coaches. I think that this might have been mentioned once earlier.
The Railjet video at
https://youtu.be/BpRAtQth9Ew shows a walkthrough of an early Railjet. The early Railjets had Bistro cars with longitudinal seating and small tables. These seem a likely inspiration for the café cars in the California/Midwest order. The later Railjets have Restaurant cars with transverse seating and tables as shown at
https://youtu.be/mJUqi6wbs2g. Both the Bistro and Restaurant cars have a First Class area with wheelchair positions, an accessible rest room, and an information booth in addition to the food service area. The 2+2 seating in Railjet’s Economy class and the 2+1 seating in the Railjet’s 1st class parallel the Smart and Select seating in Brightline, but with different seats.
In the cab car, there are premium accommodations with large reclining chairs in semi-private spaces. These are called Business Class accommodations and they are better than the normal 1st class seats. These accomodations would not seem a likely choice in the USA.
As some speculative math:
Using the California values of 35 coaches, 7 café and 7 cab cars, you get 7 seven-car trainsets of 5 coaches, 1 café and 1 cab car each. That results in 49 cars total. The Midwest values of 54 coaches, 17 café and 17 coach/business class would result in 14 five-car and 3 six-car trainsets. The total for the Midwest is then 88 cars for 137 total cars on the combined order.
