Yes. I ended up abandoning handbrake for a lot of reasons. For a long time its libraries were horrifically out of date (it was many many major versions behind the x265 trunk) and I don't feel like its "presets"/"batch mode" works properly. I always felt like I was second-guessing whether my manual settings were getting overridden and replaced by presets when inserting a batch.

I could have dived into the log files and looked more closely at what it was doing but, eh, I'm at the level where I just want a batch script where I can see exactly what it's doing upfront. If I want batching/task management that is more advanced than a batchfile can do I'll set up SLURM workload manager.