I realized today that Ohsugi is basically Faz from "Shortpacked" given human form.

Same here. I think for once this will actually make Ohsugi relevant in this series, instead of his slap-stick comedy, because once he learned about the secret of KRC and Zodiarts and Horoscopes, it'll make his employment at the school that much more interesting.

Thing is, as interesting as Ohsugi learning about the KRC and Rabbit Hatch is, you have to remember that he's the only antagonist for Gentaro and co during school. Make him buddy buddy and the KRC could essentially get free reign/unlimited excuses.

oh great - their teacher is krc member

That's SUPERVISING INSTRUCTOR to you! *snaps suspenders :)

At the least, Ohsugi looks like he'd fit in with the other nut jobs in the Kamen Rider Club. :lol