I am not aware of an overview, only the warning text on the infrastructure tab to not create endpoints and zones there.
The reason for this recommendation is, that icinga2 needs to know the zone already during configuration validation to read local files and synchronization working probably.
So my recommendation is to only configure this “infrastructure” in file, so zones and endpoints for all masters and satellites, one global for the configuration shared between masters and satellites, one for linux agents and one for windows agents.
Also the API users I create in file typically located in
/etc/icinga2/zones.d/master/ as it allows to define finer permissions than the director UI. All other objects I create in the director if possible! So sometimes a command is so special it can only be created on disk and in very rare cases also an apply rule for something else, but I try to avoid this.
With only this very little configuration is on disk and no problems with conflicting configuration should happen, so after a reload of icinga2 and a kickstart run, objects should be available in the director. This is necessary at the start to use the zones and commands and can be repeated without problems every time something on the disk changed (including an update changing something in the ITL).