Herald of Ice for spells - is there a point?

I've played it in non-crit Ice Nova/Prolif builds. The damage it adds is significant when you have upwards of 400% increased spell/cold/elemental, and the AOE damage is ridiculous when you run it with increased AOE and Cold Pen. When everything's frozen due to Elemental Proliferation, Herald clears the screen as soon as one guy dies.

It's not great when you just throw it into a build. When you build around it, it's incredibly powerful. The drawback to that power is that a build with dozens of giant, simultaneous Herald explosions will also cause constant screen freezes.

My flame totem + gmp gains 400 tooltip dps with lvl 18HoI

Hearing the sound of glass shattering as Glacial Cascade rolls over a group of enemies is pretty satisfying. I shatter 90% of everything I kill, and I've used various skill setups; Inc AoE or Conc Effect, both of which a also works on HoI. Can do some pretty hefty damage.