> I feel like one thing they could do to promote Firefox OS would be to make it possible to run Firefox OS applications on Android; create an installer/app store that would allow you to install them as if they were native apps, but they would be using a shared runtime.

Good news! That already exists in Firefox for Android, it's called Firefox Marketplace, it works by packaging up the apps as apks, which means they can operate as native android apps with access to native device APIs.