Nice model!
I don't understand why Kato hasn't jumped up to produce a UP or NS executive train. With UP, many of the cars are already done - as well as the locos (E8's with some slight alterations). Most of the remaining cars are based on cars they already make as well.
They really just need to do the Idaho (or other) inspection car or business car; a power car (they are all based on RPO's with different window arrangements), a skirtless sleeper or two. The dome, diner, baggage (used as a dance floor car), coaches are all basically used as-is.
