Config reset must set all fields in the config to appropriate defaults. If some fields do not have defaults then this is an error!
Make sure that initial load after reset does not modify the config.
Test that config saving and loading works. Must make sure that only deltas are being written. At the very least checksum will be written as a delta since it is not part of the data.
Test that when eeprom content is corrupted, loading of config fails.
Test how the delta packing code behaves when there is not enough memory. It should correctly return error when config can not be saved.
Test that system works the same way on flash based memory (where erased value is 0xff) and on normal eeprom where eraced value is 0x00.
Test that loading of configs works as expected when eeprom reads fail
Test various fixups.