My review mate. :)
Besides : Chuunins are student characters, unless you want him to lead a squad. Though I would go for specialized Jounin then.

1. ) I find the history a bit short. Mind to expand it a bit? I rather would want it a bit more expanded as it seems a a bit short. I ask this cause I know you can do so much better with your skill. ;)

2,) Bo Style • Shatter
Each weakness must be told and be clear. People need to be realistic with their characters and can't instantly know the weakness. Observant and intelligent characters may do some hypothesis and such, but that is about it.(I won't even go on sharingans or such that can predict/see through a jutsu) 
Besides, a second is maybe too fast for an 'unpredictable' jutsu. I would go for three. Else it would become more like a whack-a-mole on a distance technique.

3.) Bo Style • Gliding Pole
Sounds more like a C ranked technique. Also, how fast does it allow him to go about and such?

4.) Bo Style • Earth Shower
Sounds more like a B ranked technique to me. Also, the amount is a bit too high with the fact he can control them and with a whack turn them into a shrapnel grenade. (Earth shattering around due an implosion/explosion causes some mean and very sharp rocks to fly about. In other words, a similar kind of shrapnel grenade effect.)

That is for now my review. Hope you have something with it. :)