I have a doubt… In my use case I need to implement an application deployed on SAP BTP with Fiori UI. 
Due to customer restriction I need to read and store  all data on an S4 Hana on premise via custom oData services.

However the app will be integrated with other BTP services like process automation, document management etc
Since I will not have any data on cloud (no Hana cloud instance) for the moment, should I go with simple Fiori app or CAP offersy more advantages?
In my opinion one advantage of CAP could be the security enforced by the backend service that masks the api calls.

Any suggestions?
thanks all

I tried both approaches, one is simpler the other is more flexible