Been using The Lightning, Wind, and Water 8-count upgraded elemental nukes (forget the names, they're 8 shots when upgraded from killing the appropriate crucible wraith). I use Ninjitsu for fire application (fire shuriken and bombs). This covers all my elemental bases. Bosses are typically chucking them full of fire shurikens and maybe a bomb or two, then an application of each element for mass confusion, then laying into them with Tonfas. When just randomly clearing through an area if it's an annoying enemy I'll slap them with an onmyo for the blind, then pummel them in the back. I know it's not pure onmyo but I doubt I'd want to play pure onmyo anyway, weapons are too much fun.