you cannot access them without checking they are set, as you don't enforce it in the configuration class. there is 3 solutions to avoid errors:

- add default values in the configuration
- mark them as required in the configuration class (which would make it impossible to use your shortcut notation for id-based config as these settings would be missing)
- throw an exception in the DI extension when they are not set (equivalent to the above case, with a dirtier code and the same limitation)