Matsui said in a recent interview that upgrading Aegis and Ochain to i-level would cause a loss in magic evasion (which is the theme of most I-Level content). I would like updated Aegis/Ochain, but not if they're inherently weaker than their 99 counterparts in some way. Anyway, Matsui said it was "a future task for the battle team" and I hope they come up with something soon. (same for Beastmaster too).