I was thinking something along an Adamant nature with 56 Hp / 252 Atk / 228 Spe EVs. This lets it outspeed Adamant Excadrill in Sand at +2 while giving it enough attack to murder everything. If you aren't worried about weather benchmarks, you can just dump it all into HP and Attack since at +2 speed it outspeeds timid base 150s. Mostly I think it would just benefit from the extra attack, but I haven't had time to really test it, so I can't say from experience if Kyurem needs the extra power.
EDIT: Okay, I really tried going down the Viability list for something that would wall Kyurem at +2 Atk and +2 SpA without investment, and about the only thing it might secure an extra kill on is Scizor, aka the one thing you shouldn't set up on. So, while an HP and Atk spread would give it more usefulness outside of when WP activates, admittedly once it goes off about the only thing on this earth that will stop it is Scizor and Mach Punch users regardless of 252 attack EVs or 0.