Honestly I feel like Lucy will give Brandish a run for her money

If Lucy can use the powers of her lessor spirits like Hologrium to negate effects of magic and able to use it at any time it might be great for her. Plus we have yet to see her other powers. However, brandish may be my fav villain of this series so far besides King Jelllal
My theory of Lucy being light oriented and Natsu being dark oriented may be right
Think of it guys. Why was Lucy the ONLY one to survive Allegria? I don't believe it's luck but it has more to do with her Celestial Powers being powered by her trust and bond with her spirits hence why the spirit king could banish the dark meaty mass aka Allegria.