Type in chinese, let's see your standard before we go any further.
read my guide here:
My honest answer would be that if you figure that your chinese is starting to become sub-par, drop the higher chinese.
Don't waste your time unless you have the interest.
I would say that you would need at least 50/70, I would recommend memorising the format for composition well, even if you have nothing to write, just follow the format, throw a few su2 yu3s in that can be used for almost any question, and you should be good to go.
For oral, nothing helps like practise. You should keep bugging your teacher for consultations and put in a lot of hard work, imo chinese is "muggable" unlike english, so do work hard.