What's the best option for a mixed set (EVs, moves, etc.)?
I've been using:
"Dora The Explorer"
Sazandora@Choice Scarf
Nature: Naive
EVs: 152 Atk/ 104 SpA/ 252 Spe
-Draco Meteor
-Crunch/Dark Pulse
-U-turn
-Surf/Fire Blast
Though the Mixed Scarf is perfectly viable and I don't have any changes to make to yours (except you have to pick Crunch or it should have 252 SpA/252 Spe, not worth splitting just for power on non-STAB U-Turn,), I went the Life Orb wallbreaker route - Draco Meteor/Outrage/EQ/Flamethrower (Surf would be a fair choice too, but Nattorei likes to stay in on her even if I switch into it!)
takes advantage of superior defensive typing/bulk to most other wallbreaker options, the other moves providing coverage for steels. With that, max speed doesn't really make sense to me, since you still get beat by too much. I'd rather split the offensive EVs, a bit of speed to get past some slow things, and rely on your natural bulk. I think I went max attack and than EVd to beat max speed Tyranitar - whatever it was, it wasn't that much. the rest went into SpA.
and she gets 2 kills per battle with shocking regularity. Walls coming in will have to take a hit and then another hit from the opposite side of the spectrum before they can do anything. Sweepers that can't OHKO are generally OHKOd back, and very few things are capable of doing so. I personally provide paralysis support and like to bring her in on a resisted hit from a paralyzed sweeper, because that's pretty much a guaranteed kill, but the set works fine without it - you've got other things to switch in on.