Thanks for replying.

Do they really need suburb tagged?

It's already discouraged to add addr:city to most addresses since suburb boundaries are already mapped. In this case the level crossing is on the border of two Suburbs https://www.openstreetmap.org/relation/3173338 and https://www.openstreetmap.org/relation/12079778 but our suburb boundaries are not that accurate and features near the border are more ambiguous.

Regarding the source, I just think that it's misleading to add the source tag as you have to existing level crossings, as the source for those was likely not TfNSW's Open Data but organic OSM mappers from local knowledge, ground surveys, street level or aerial imagery. So best to just set your source on the changeset level not the each level crossing feature.

Good to know you've updated your dataset, apart from applying names were there any other discrepancies you've found?

Would it be worth me updated the Map Roulette challenge at https://maproulette.org/browse/challenges/49134 with the new data? Otherwise what process are you following, are you just going through each of them manually and comparing?