Yeah, when you need it, the ApplicationArea property is great. But when you are developing a per tenant extension for a customer, of an app for app source where it's all or nothing (if you install it is because you want to see all fields/actions added by the app), having to add ApplicationArea = XXX to every single element becomes just visual noise, and even if you have some elements with a different ApplicationArea they will be hard to notice because every single element in the page has that property.

It would be nice to be able to specify a defaultApplicationArea in the app.json (which might not be All, depending on what the app does), so that any field or action without a specified Application Area is assigned to it.

P.S. I'm not adding an idea for it, but DataClassification is in a similar situation. I can see why you want us to be sure that we assign the correct DataClassification for each field. But really, if most people just copy/paste DataClassification = CustomerContent without a second thought (because that's the correct value 99% of the time), how is that different from just making CustomerContent the default and just letting us specify a different value when needed?