As one example of this (this same use case can be applied to any "association" type of activity where you apply a scheme or other item to a project) you should be able to apply a notification scheme to a list of projects that you select instead of having to go through each project one by one making the same change to each of them.

Beyond just projects, as a general best practice for good user experience, wherever it is possible there should be a mechanism for making bulk changes where you choose the pairing you'd like to do for one project and then have the option to apply that change to multiple projects, multiple users, multiple pages, etc.

I'm just envisioning an interface where instead of you going into the the project to make the change (such as adding a notification scheme) you go into the notification scheme area, choose the scheme you want to use, and then select all of the projects you want to apply that scheme to. I'm sure, as with most things, this is easy to envision but probably very difficult to program and implement. But maybe one day?