Just to let you know, I'm changing some of the arc names for consistency. Some of the names you came up are good, but feel little random and not so concrete. The arc name should explain the arc better. You got some of them right, like Machine Banchou Arc, Five Dark Vows Arc, but others feels out of place like Unknown Relative Arc, etc. The arc names are usually: name of item they are after; name of location; name of main enemy. In our case the best option is "main enemy", so I'm changing Meeting Akira -> Iai Banchou Arc; Cult of Raionji -> Nenbutsu Banchou Arc, etc. Also splitting The Dark Student Council Arc in 2, since otherwise the arc is half the series and it do feel like the arc is made from 2-3 smaller arc, so The Dark Student Council: Hakai Banchou Arc and The Dark Student Council: Nippon Banchou Arc. I have also talked this with Zange, and he agrees.