Dave I imagine you could utilize the chassis for the 4 wheel 20 foot wagons for cement, bagged cement, beet, ballast etc. A 22 foot 6 inch 12 foot wheel base wagon with outside w irons would be nice for 20 foot containers, Guiness kegs, weed spray train (older type) etc. A decent chassis for a 30t brake van would compliment the SSM kit.
If they are easily adaptable for 21mm then all the better. As much as I hate to say it (because they replaced my beloved Cravens) a 2700 would be nice for my layout and the period I am modelling.
Rich,