Yeah, this definitely requires splitting state-impactful activity into its own function. That's good practice anyways, though I understand it might be a pain in large codebases. Regional tags are definitely an interesting alternative!

For the UI example, I don't think you'd use durable execution for most of the UI--it's just not needed. But maybe there's one button that launches a complex asynchronous background task, and you'd use durable execution for that (with careful workflow ID management to ensure idempotency and allow you to retrieve the status of the background task).