Arcanes you'll want on Shadow are Energize and Strike/[Fury]

As of writing this (30.0.2) the gladiator set bonus doesn't affect the claws, and since you can't equip acolyte mods on exalted weapons because of Scott's moon logic, Sac Steel is the only CC mod available to you. This is a heavy attack focus build that can get you somewhat comfortably into red crit territory on it's own, but Avenger or [Cat's Eye] certainly couldn't hurt. P. [Fury] can be replaced with Berserker if preferred.

Also, dont run Amalgam OS over regular OS if you already have [Killing Blow] in your build. KB will practically get you to the Wind Up cap on it's own. You'd be trading off extra damage you will notice for extra Wind Up you'll need recording software to notice.

Stay frosty, Lads.