Ecosystem contains configuration files for game areas and for the Placement and AutoPlacement systems (which statically or dynamically spawn actors).
LevelSensor.byml is the main configuration file for the LevelSensor subsystem (which handles parts of difficulty scaling). All information related to difficulty (enemy and weapon) scaling is stored in this configuration file. The file format is BYML.
LoadBalancer.beco is a beco file. Its purpose is currently totally unknown.