Well today I discovered that it is 100% possible for trams to carry cargo, given the proper stations. With that in mind I'd like to introduce an American Interurban Railway set.
I'm planning on doing the following:
-Generic freight motor (single car, double car, triple car w/trailer. Max speed 50 mph, introduced 1905)
-Generic steeplecab (hauling standard-gauge freight cars, probably not until after USA DLC is released because I don't want to make railroad cars someone else has already made.)
-Generic wooden interurban (max speed 50 mph, introduced 1905)
-Generic steel interurban (max speed 70 mph, introduced 1925)
-Pacific Electric "Blimp" car (max speed 80 mph, from 1-5 cars)
-Chicago North Shore Line Electroliner (max speed 100 mph)
-Freight stations for tramways
-dedicated high-speed road for tramways (not sure how feasible this is)
All of these will be coded as trams initially. Might make some regular railroad versions later if there's interest.
so far I've got an old wooden interurban model, untextured. Gonna try and make this into a workable freight motor as well and then do a really basic release with those two plus some infrastructure for them.