Ability to supply per_page parameter on API endpoints
The fact that the endpoints have a set per_page amount hardcoded for pagination makes things very inefficient. For example, we have over a hundred products in a particular category and our web application uses the RepairShopr API (proxied) to retrieve a list of all those products.
Since the static per_page value the API uses is 20, it means the application can only retrieve 20 per call. So it ends up doing like 15+ calls and taking over 30 seconds to load the basic data it needs.
If the client could specify how many records to return per page, it would probably also reduce server load on RepairShopr as it would mean clients no longer need to flood the API with requests just to get all records for something.
Probably useful on all endpoints however the one we're using in this example is GET /products.