I was inspired by another recent comment you posted on HN, and after some testing of the Textract console [0] I wrote a simple "local only" command-line version [1] (Python, boto3) that does similar things to your tool.
I used my tool to OCR a few hundred comic strip images I've been meaning to OCR for a while now - the service did beautifully where other tools I've tried in the past struggled with the handwritten text on the comics. Textract is fast enough that running serially was fine for a one-off without involving the more parallelized S3 workflow.
[0] https://us-east-1.console.aws.amazon.com/textract/home?regio... [1] https://github.com/mbafford/textract-cli