Support build help

Hello everyone so with the new bosses and level cap going up and bless becoming less effective now I'm restarting my support Mage, I want to focus on mainly support, no impact and no storm. I need advice on where to allocate my stat and skill points.

For example does mini heal scale with the target or the casters hp? If so should I invest points in vit? If someone could post a updated build I would appreciate it very much ^-^