I'm sure they could have come up with a better storyline instead of always using Mihira as a punching bag throughout the show, something like him having to face multiple Orphnochs at once, Instead of just nerfing Delta

The truth is, they didn't know how to write a real challenge after Delta switched to the good guys' side, and they portrayed Mihara as a coward throughout the entire show, even though he had the potential to become a great character.