Page Field autosave strategies and dependencies

[Kiwi Chris]

What options are there to autosave individual page fields both in normal pages and repeaters?

I see there's a page Auto Save in pro dev tools, but I'm not sure if this is what I need?

There's also a commercial module by Kongondo - dynamic selects, but that requires creating a new field of type dynamic select, rather than existing fields, and I'm not sure whether it allows autocomplete rather than dropdowns, so it's not ideal.

Mainly my use case is to handle dependent page fields, where one page field depends on the value of another one. 

I'm aware of the ability to create selectors that refer to other fields on a page, but this doesn't work as required in all scenarios.

I know the API allows saving individual fields and can do so silently if necessary.

Having the ability to specify individual page fields that should autosave via ajax when they're updated would be extremely helpful.

Where this would be particularly useful would be with page Autocomplete input fields, as I've worked out how to hook input to pass the calling page to the hook, for custom selectors, but this only works with current values already saved to the page, so being able to combine this with the ability to autosave specified page fields would help with complex dependencies.

For some fields this functionality might be unnecessary or undesirable, so being able to configure it on a per field with per template override as with other field properties would be ideal.

Has anyone implemented anything like this, or does the pro page Autosave module do this?