Moneyinfo provide a practice specific client mobile app and branded browser portal, fully branded, for valuations, open banking, secure messaging, assets and liabilities. They have an API already, albeit the API is only available to Enterprise clients. I know they are also working on the fact find currently.
Rather than plannr doing the same, or waiting until plannr is able to do the same, it could be an option to integrate with moneyinfo. This would indirectly provide moneyinfo users, through the integration, valuation feed data for a large number of providers plus open banking without the need for plannr to complete the valuation feed build of the same large number of providers. I accept moneyinfo could be seen as a competitor so it may not be an avenue you wish to explore!