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Pidgeot is my favorite Pokémon, but I don't think it will ever be competitively viable short of radically changing its base stats, giving it a ridiculous Mega Evolution, or giving it a god tier ability. I wouldn't be that surprised to see it get a Mega Evolution, but it probably still wouldn't be that good.
As for abilities, even Speed Boost wouldn't make it a top tier threat. It would need something like Huge Power or an auto-inducing ability for a new Flying-type weather.