From the description it look like Facebook Home is more than just a launcher. I have use a ADW.Launcher and NOVA, yet the notification interface is the same as with Samsung's gawd awful TouchWiz. FBH looks like it's got it's tendrils into the messaging and notification. Who knows what else. Just switching launcher doesn't mean all of the FBH services are switch off. Last thing I want is a background service surreptitiously sending my personal info to the mothership.
The only way to exorcise it would be to root and use Titanium Backup to uninstall it. Then you'd have to take your chances to see how much it was integrated into the ROM. No. The best option is a custom ROM without the stench of FB anywhere near.