Really, this pokemon screams for a good 3rd coverage move like earth power or focus blast (a lot of pokemon get it anyway). I wonder if it could learn dragon pulse (it's an attack done with the mouth, a bit loke hyper voice.).
I would run an Adamant set if it had swords dance, EQ, U-turn, because that would be enough to go physical. Wait nvm, it doesn't have the bulk to set up with it.
Also, this guy learns yawn. Not sure why he does, but it seems a better option than Noble roar to me. That would give you the option to phaze with either will-o-wisp for physical attackers, Toxic against stall, and Yawn as a general deterrent. Does anyone know if yawn infiltrates substitutes?
I've been thinking, can't he find a niche as a suicide lead? I was thinking of this:
Pyroar@Focus sash
Timid Nature
252 Sp.Atk, 252 Spd, 4 Def
Ability: Unnerve (does that even matter at this point?
-Overheat
-Hypervoice
-Endeavor
-Yawn/Dark Pulse/HP fight/HP poison
Overheat is to just blast your opponent away. Use apropriate judgement for the right timing. Hyper Voice is the move you will mainly use, since it coverage isn't terrible. Endeavor is for that moment you feel someone will oneshlt you, otherwise it won't end well. It's currently one of the fastest pokemon, so endeavor won't be used too late. Lastly yawn is to cause some switchins, whilst dark pulse takes care of ghosts, notably Aegislash and M-Banette. I mentioned Hidden Power, because HP fight would give it some coverage whilst hp poison would deal with fairy types, notable Carbink (then again, with those defenses you might just go with hypervoice.). Overheat roasts both Klefki and Cotonee. I forgot to mention that taunt and roar are also good alternatives.