Divine Blast (supports where?)

Have been using Purifying flame and chose to use Divine Blast as my off-skill since I can use mh/oh to scale each independently. I've noticed that there are VERY FEW venues to scale this gem, both on the passive tree and with supports.

The only way I can see scaling it right now is purely through the shield value. Or generic crit.

It is an attack
It is not a projectile (can't use any projectile attack supports)
It is not a melee attack (can't use any melee attack supports)

What other kind of attacks are there?

Only generic untagged (no spell,attack tag) supports work with this skill of which there are <10, maybe even lower, which actually scale the damage.

Right now its a essentially a trap skill, but without the scaling.