>> if you have files named, say, A, B, C and you apply a batch rename that's going to call them instead C, B, A, you get errors
I've encountered this a lot, probably because I've tried many different naming conventions over the years and have 60K+ files to deal with. I'm not aware of any logic in MC that triggers multiple renaming passes.
My solution is to just run the Rename process as many times as MC requires before it stops giving errors. I'm typically working with a subset of tracks, in a view by artist or similar, and getting the filename correct involves a complex Rename expression because my file path/name uses Artists (a custom field), Genre and Rank (another custom field) and certain manipulations.
Each Rename pass gets at least some files renamed as I desire. 99.9% of the time with multiple runs MC eventually properly renames all the folders/files. In the 0.1% case I give up and manually rename by editing the track's filename field. Then I run Rename one more time to be sure MC is happy with my change.
Also, Rename can clean up filenames with (1) or similar MC changes trigged by dupes that no longer exist so it's a big help cleaning up. However -- caution -- if a dupe really exists, multiple Rename runs can sometimes flip the (1) from file to file, then back again, forever. This requires manual intervention.