KXA and some of the taller containers for the DRS nuclear flows, as used currently and for the past few years, would be nice next additions to the range, with more DRS PFA numbered wagons to match.
As nice as the DRS PFA low height containers are, I cant find any reference to them being used after 2015 as the traffic started using the taller containers around then. Hopefully, the next batch of PFA's might lead to some variations in loads. Hint, hint, no rush, Fran & Co.