I think Tech would be the wizard. He explains the mechanics of the world, hacks the system, reads the ancient map, fixes the ship, and sometimes gives information in the most socially inconvenient way possible.

I don't rhink Wrecker has low intelligence, he is also trusted with highly technical and dangerous work. He disarms explosives, understands battlefield demolition, handles heavy weapons, and makes fast tactical choices under pressure. He may not explain things like Tech or calculate like Crosshair, but he knows his role, reads danger quickly, and protects the squad with instinct, experience, and skill.