I would leave it where it is for now. Just work with your vcore until you end up getting to hot of temperatures or have increased so much that you think something else may be needed.
It really can take 5 or more additions to vcore to get blend stable. I was running all stock voltages except for VDDA @ 4600mhz. If you are really worried about it you could put cpu/nb at 1.3 and leave it but then you're just adding voltage without knowing it really did anything and the goal is to have every voltage as low as you can while being stable.