Isn't it a bit early for side plots? Have a main event where everyone gets involved that explains to the characters the actual premise of the academy, it's curriculum and training methods. We as players know what a hybrid is and how it works, but our characters are on their first day; they need filling in. It'll also allow some room for groups to split off and talk between themselves, make friendships/rivalries before you move onto a major plot point. After that, then maybe side plots could be investigated. But jumping into characterisation arcs too early? Nah.
I'll post this evening after work.