But, I see it's not automatic - every time you want to create a new page with any sort of default values, you have to explicitly select the content template? Guess that'll just be an education for the customer.

Might just be 'easier' (from an editor's perspective) for us to hook into this and manually force the issue: https://docs.umbraco.com/umbraco-cms/reference/notifications/editormodel-notifications Of course that means the default value's no longer in the CMS, but maybe better than leaving the possibility that the editor does it wrong and then complains.

Still, so much uglier than just having a 'default value' textbox on the property definition. Pity, that.