Update document library content types in a SkyDrive Pro (Mysite) on Office 365 programmatically

In Office 365, I'd like to update the content types of the default library created under the SkyDrive Pro whenever it is created the first time. I see a few challenges:

1. Triggering an event whenever the library is created the first time

2. Creating an app or traditional SP solution that would be loaded and executed automatically (and with high enough permissions) on each site. In this scenario, the users wouldn't be installing the app.

Any specific guidance anyone can provide? Remember, this has to work with SharePoint Online.

Thanks!