OK, here's a radical idea....for example....
Santa Fe's Trains #7/8....The Fast Mail. For 45 years these trains hauled the mail from Chicago to LA, often having a length of 22 cars...or more!
OK, OK.....so they weren't your typical passenger-hauling train. In fact, they typically had but a single 'rider' car...a lowly heavyweight smoker/lounge or coach bringing up the tail end of looonnnng string of baggage, rpo, express boxcars, horse express cars, etc., of all sorts and makes. But, think about it...
So, here's the crazy rationale....
First, head-end cars get short shrift in the model offerings. They're ho-hum, boring, yawn-worthy, homely, dime-a-dozen. etc., etc., etc.. And, yet, they were immensely critical and numerous on the 1:1 rails through much of the 20th century. It's how the mail was moved, man!! And there were whole trains of these duckly uglings, running coast-to-coast....on regular schedules.
But from a model production perspective, they're sort of interesting....I should think. Hey!...no windows!! No interior lights!!...except, perhaps, on the rpo. No plethora of peoples. A few doors. Ho-hum paint/graphics. And so many variations of baggage-hauling types/makes/lengths/styles/etc., with every single daily run of #7/#8 having a unique mix of equipment.......Why, how could ANYONE argue the authenticity of the mix!?!?!? As for the rider car?......pick something appropriate. And just DARE someone to complain it's wrong!! Heavyweights, lightweights, ACF, Pullman-Standard, Budd, this class, that class......Holy Moly how can you miss????? And the possibilities and volume potential could be ginormous!!
And the Atlas, MTH, Lionel folks could do the other complementary cars for the Fast Mail that fit their production portfolios....Express Boxcars, single door, double door, 50-foot, 40-foot, appropriate mail-hauling colors, .Allied Full Cushion express trucks, .....Mercy!....it's mind-boggling what a focus on mail-hauling trains could do for this hobby....(and my wallet!).
(I tried to get the HO production crowd jacked up over this about 10 years ago........the groaning was more prevalent than the resulting product!.....How Ordinary)
And, I only pick the Santa Fe's mail-hauler. I KNOW that they were as prevalent on eastern roads, too. Which simply becomes a further multiplier of the possibilities.
I know.......dumb idea, right?
Not necessarily.
Something for rumination.
KD