You know, I don't see how Yorihime is so unbeatable and ultimate. She didn't actually shoot any bullets, she just used her flashy powers to deflect the girls' patterns back to them. Is that supposed to be sticking to the rules of a duel? Plus, the girls themselves didn't seem to put any effort in winning whatsoever. It's like they didn't want to hurt Yorihime, they just wanted to show off. Take Sakuya for example. Compare her performance to EoSD, where she fought to protect the mansion. Hell, she even came back, beaten and exhausted, with a spellcard called "Eternal Meek" in a desperate attempt to kick your ass. Here, she does nothing and even casually smiles after losing. The difference is huge. She has no reason to try, after all.
That whole battle in the last three chapters of SSiB looks like a friggin tea party. No blood boiling, no intensity, no danger, no suspense at all. Just "hahaha let's have a fight, hahaha I lost, let's have a cup of tea now"