I thought about using this build built around Boil Blood. Not that I expect it to be anything but bad, but a switch up could make for some interesting play, especially trolling necros.
http://is.gd/UVm9TE
(link doesn't work, but basically a tribrid build with a focus on upping lightning magic damage through general and getting purge, while keeping detonate and possession at 1 point.)
I'm time training the perk, so anyone know if it crits of off Hand of Doom? If it does, there could be some merit for this perk. Especially since some of the newer gear (and gear to come) is focusing on one magic damage type, it might be possible to get lighting damage focused sets soon, especially after the crafting revamp.
If you can get your lighting magic damage to a stupid high level, and if you can force crits through hand of doom, it might actually be viable facing multiple target encounters.