I just completed Stonefalls, which is a VR6 zone for me. I entered the zone at almost exactly VR8 and it took me to almost exactly VR9. To be precise, I gained 1'030'000 XP.
I completed everything the zone had to offer, but only once (Dolmens, delves, the public dungeon, etc.).
I didn't avoid any mobs in my way, but I also did not grind.
The only achievements I completed were related to the zone (of those, I completed all except fishing).
During this time I did not participate in PvP or any dungeons.
Conclusion:
1M XP per VR is just right. People who do not wish to finish an entire zone will have to substitute the missing XP through grinding or dungeon running, but completionists' VRs will always be aligned to the zone they're in.
I wrote this down to end the debate about post 1.5 VR progression and hope to have put some minds at ease.
Victoria Lux - Templar Tank
{EU/DC}