I only use mixed attackers during the main story. The reason for that is that EV training during a normal playthrough would be too much of a hassle, and if I play the game normally, the EV gained from defeating other trainers/wild Pokémon would be uneven. By using mixed attackers, I can guarantee that every single stat will be put to use. It feels like a waste gaining Sp. Atk EV on a physical attacker.

Please share your autism so I don't feel that bad about myself.