For a line experiencing a SafeTrack surge - only use train cars that have ample handrails.
Some trains have minimal handrails near the doors, it seems that the point of these cars is to promote passengers to move the center of the car. However, with SafeTrack - given that fewer trains are available, passengers have no option but to stand/cram near the doors. For many passengers there is nothing to hold on to, or it makes for an extra awkward travel experience. This is a small but feasible change - it is not going to make a drastic difference overall, but will enhance individual rides.