Complex form interactions

It would be great if form interactions could:

• Retrieve data from another model, like in a workflow, which can then drive further defaulting. For example, look something up in a reference model based on a relationship and pull that in as a default.

• Trigger an integration and bring something back. For example, lookup an accrual-based leave balance based on input dates from a 3rd part-time & attendance system and then display that back in a computed field.

Having something a little bit like a mini workflow with lookup and if/then actions that are run asynchronous as a background form would be fab. It may need an option to be blocking or non-blocking in the UI. For example, a background calculation may block form submit but allow other field entries to continue, whereas another might block form entry whilst the event is happening; another might be informational-only and entirely non-blocking.