Use two different json files. Original, and Desired and it will generate a patch file output. https://json-patch-builder-online.github.io/ This one tells you what the difference between two files are. https://www.diffchecker.com/ This is useful to validate JSON and patches (no comment support) https://json-schema-validator.herokuapp.com/
As I've recently started modding, I've noticed it's very helpful to just completely overwrite the existing game files while working. After everything is completed, I go through the files and use the patcher at https://chbrown.github.io/rfc6902/. The one you mentioned works as well. I usually just do small patches manually though. It's worth noting that validating your JSONs before booting up Starbound will save you a ton of time going through logs for simple syntax errors.
Of course. Like I said, I go through and generate patches after I'm done working on the files. For future modders who may read this thread, I just wanted it to be known that it isn't required to work with a patch during the entire process.
