This is an interesting question, and the resulting answers are informative.
In looking at the dates of production of the EBT engines, their tractive effort was probably fairly consistant given the technology at the time each was built. C&N #30, better known as C&S/RGS#74 was built in 1898 and had a tractive effort over 21,000 lbs, not bad for an inside frame 2-8-0.
The advantages of an outside frame, allowing larger boilers and the additional weight of the frame material make me wonder if the next round of engines ordered by the EBT would have been outside framed 2-8-2 engines, as the advantages were well known and proven after the K-28's were built (in what-1923?).