I'm also a relatively recent BBF convert. Mainly for the facility of being able to focus/recompose without changing out of AF-C focus mode.
Regarding the Nikon AF-ON/VR relationship, since I didn't use it before I can't speak to how the old bodies worked. I currently own D4, D800E, D7100 and all three activate VR when the AF-ON is pressed. But I would prefer VR only activated with half push on the shutter. My reasoning being that I frequently watch/track a critter for quite a while before taking a shot or in between shots. While tracking it is often necessary to refocus multiple times but no need to activate VR until ready to make a capture. So it is wasted battery power and unecessary wear and tear on the lens to activate VR until ready to shoot. If anyone figures out a way to dissable VR with AF-ON, speak up.