Some reference material you might be able to glean information from on the future of rail transportation: Current issues of CTC Board Railroads Illustrated Mag. www.hundman.com, Railway Age Mag., Rail Pace Mag., Instute of Railway Teconoligy in Chicago,Ill to name a few. Do a Google search for web addy's. Hope that helps you out. "Still Training After All These Years"
I entertained the thought for my own railroad, albeit in HO, my scale of choice, sometime back in the early Nineties. However, I've thought about kitbashing a locomotive inspired by something I once saw in Popular Mechanics back in the day. It was a method for disposing of hazardous chemicals, which used plasma to break down their molecules into harmless substances. The whole assembly could fit into a forty-foot trailer. Dieter Zakas
My O scale 2 rail layout is set in the future so that I can use my "derated" GP60 for switching. Somewhere between 2050 and 2040. Also UP never took over SP in my fantasy world
Wow, I really like your idea of using Acela's for motive power, and just the layout plan itself sounds interesting.
The problem with larger, heavier containers is that they will have to be carried from their origin and destination points (warehouses, usually) to the rail yards by truck. That's why they are so common, efficiency of delivery. So, they can't be too large. Right now the limit is set by the DOT at 53' long, and the combination with chassis cannot be more than 13'6" high. There's a width limit, as well. So a 53' container is probably going to be the limit. This is also why heavy trucks are probably here to stay, not only do railroads go yard-to-yard, not point-to-point, but from ship to destination, trucks are generally faster and today's American trucking fleet has more capacity than today's railroads. Not to mention that trains can't go everywhere, while trucks can. Generally, railroading containers is more cost efficient than trucks only over long hauls.
good bet it will be unit trains,intermodal,and all pulled by one railroad THE AMALGAMATED CONSOLIDATED AND DIVERSIFIED NORTH AMERICAN TRANSPORTATON SYSTEM.