Pre-populating Answers and Repeating Sections

In my organisation, forms need be signed-off by several levels of management before they are complete. If they're unsatisfied with anything, this can be passed back to the previous stage. This means I need to save and recover the current answers, then pre-populate them in the form at each stage.

Currently I do this by saving answers to a SQL database, then recalling them as a comma delimited string and using a substring to 'cut up' the answers. I did try extracting each answer as a row in a Collection (by using a Pivot table in SQL), but this required a separate variable for each element and in larger forms, lead to the workflow being too large to save.

There doesn't appear to be a way to do this with Repeating Sections. I can't find any way of specifying which index you would like to refer to within a Repeating Section, and this also makes saving answers very difficult (though I found a method of doing this).

To pre-populate answers, you'd need to consider JSON, comma delimited lists as an input, or at least allow users to specify an index. Specifying index 4 for example would allow the user to per-populate the 4th instance, and create instances 1-3 if they don't already exist, to ensure it's in the correct place.

A general 'repopulate using previous answers' option would be ideal - similar to what Survey123 does, but integrated into the workflow. In my mind, it would bring back the form in the same state it was submitted earlier in the workflow, with all the answers pre-populated.

Ideally it would also work within loops, to allow the user to create a workflow which loops through different levels of authority, while keeping the current answer set.