At this point, given the team took the offensive route, I figure the team could do well with two things added. A ghost type like Misdreavus, to prevent Rocks from being setup / to absorb Fighting hits for Piloswine / spin block for Piloswine's Stealth Rock. The second, is something that outspeeds boosted Pokemon - perhaps a Scarfer like Rotom-F, Raichu or Mr. Mime.
So, for my first recommendation, I'm nominating Misdreavus. The minimum speed that it should run is 263 speed, as this outspeeds Onix and Solrock by 1 pt (Onix is especially important to outspeed because Dundies' Sun team is rampant on the ladder right now). I normally just run max speed Misdreavus, because its Taunt also outspeeds Monferno, which can setup Rocks and hurt Rapidash that way.
Misdreavus @ Eviolite
Ability: Levitate
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
- Taunt
- Nasty Plot
- Shadow Ball
- Hidden Power [Fighting]
You can change the EVs on Misdreavus to make it bulkier, but the most important thing is to stay above 262 Speed to stop Onix's Stealth Rock, Taunt and Sunny Day, like I mentioned above.
This also happens to lure out Ninetales, as your opponent may expect Will-o-Wisp. You can double out to Rapidash, then Drill Run if it stays in. If you remove Ninetales quickly, Leafeon will have a much better chance of sweeping too, so that's always a plus.