miniExtensions Form has a feature called "Redirect to Airtable field". It allows you to redirect users to a URL in an Airtable field, which can be customized per user.
It can contain a formula, which could be made out of any logic. E.g. you can redirect users to a different second step (e.g. another form) based on their answers in the first form by creating a formula in Airtable. You can find this feature in the advanced section.
You can show the users their previous submissions by redirecting them to a formula that automatically takes the users to their own custom portal view (or results page).