The app builder should consider two things before overriding standard buttons:
Standard buttons can be overridden with a Visualforce page. A Visualforce page is a web page that displays custom user interface elements using Visualforce markup and Apex code. A Visualforce page can be used to override a standard button and provide custom functionality or logic3.
Standard buttons that are not available for overrides can still be hidden on page layouts. A page layout is a layout that determines how fields, related lists, and buttons are arranged on a record detail or edit page. A page layout can be used to hide a standard button that cannot be overridden by removing it from the layout4. Option A and D are not things that the app builder should consider before overriding standard buttons.