I realize, Sgt. CNJ, that the Slumbercoach design does have its fans around here, and I further realize that it was the only economy sleeper arrangement that ever made a dime for any road (all others, including the Touralux on my MILW, were flops).
However, even after extending the due respect that you and the others who support the arrangement deserve, I must disagree.
First, let us be mindful the Slumbercoach was a product of a regulated industry environment. The fare was the fare and could only be changed after a burdensome process of seeking approval from a now defunct regulatory agency - the Interstate Commerce Commission.
Secondly, regulation notwithstanding, no passenger carrier had perfected demand pricing models to the extent they have been today. This perfection can of course be credited to (blamed on, anyone??) the device you are presently looking at.
As a result, adding any kind of economy sleeper, which allowing me to reiterate, the slumbercoach was the best of the bunch, would simply result in one more style of car for Amtrak to maintain with questionable revenue enhancement capacity. I think the best approach is to add more Sleepers perfected from the existing design, and allow demand pricing to accomodate those who "have their limits" on a Sleeping Car accomodation charge.
In closing, allow me to note that when Amtrak WISELY made the decision to have not less than two berths in any accomodation, that created the economy sleeper - it is known as double occupancy of a Roomette.