I released the updates for the 2.7-compatible version of my simple dashboard plugin this morning. Code can be found here:
It lets you turn on and off all the widgets on the dashboard, and lets you override the primary and secondary feed. It also lets you turn off the ability for the users to customize those feeds. (So, if you want to lock them to one feed you can.) It does not prevent them from just getting rid of the feed entirely, or from re-ordering.