We're all busy trying to make pretty and small intersections with the new elevated rails and curves, but a lot of best practices for intersection design still matter and aren't being applied. Buffers within an intersection that match the length of your trains (with some specific extra for accel/decel) are still an important part of making a high speed intersection. It looks like you've made your intersection with all chain signals, so only one train can be on each path through the intersection at a time, enforcing a *huge* gap between trains on your network.
Take a straight rail and put a gap between signals as long as this intersection is wide. How many TPM can go along that straight track? Whatever that number is, it's a cap on the possible performance of an intersection with no rail signals (interior buffers) of the same width.