Hi @Turntwo,
We built something similar with a pretty complex “rule-parsing-and-apply” engine which can perform arbitrary data manipulation based on declarative rules. However we integrated it outside of the UI. The engine runs on every data change and the modified data is fed back to JSON Forms.
Besides needing to solve additional complexity (e.g. what shall happen if the user modifies the data even further before the engine completes) this works fine, especially so with the middleware as it can be much better extracted what the user actually changed.
React has a lot of performance improvements with the later versions where updates are batched etc. Something there seems to go wrong for you, as the update mechanism is tied to the rendering via useEffect.
Maybe you are also running into issues with the controlled vs uncontrolled behavior of JSON Forms. Can you try what I suggested here to see whether it then works better for you?