Indeed! FTB is magical, thanks for the tip on auto-update.Can always restore diabled Amazon services with the appropriate ADB command ... afrer all, FTB is basically a bundle of ADB "tweaks" which are generally reversible.
As with any powerful set of tools (and FTB is REALLY powerful) , just because you HAVE them doesn't mean you have to USE them all.
Remember the cautionary tale of the "Sorcerer's Apprentice" ... FTB is the "magical book of spells" !
Turn off auto-updates for both AppStore and Play Store apps to minimize any update "surprises".