You mentioned it is not a show or a gig, but ask yourself, what is the harm in treating this as if it were a show or gig. If you go into any performance with the mindset you are doing an actual gig, it will give you more motivation to not only perform better, but to create a better set.
You say things are personal preference, and that is a reason for you to have your sets a certain way, and that is true, but personal preference is not always based off of fack, personal preference based off of a lack of experience or understanding is not a valid reason to "keep things as they are," but should be used to help you to improve your knowledge on performances. The advice to do card to mouth AFTER an ACR is solid advice, and you will only be hurting yourself if you open with CtM and then move onto ACR. I am not saying this impossible to pull off extremely well, but from what I have read, your experience is a bit low and might not be ready to tackled such a large challenge.
You are however absolutely right that an opener should speak for itself, and CtoM does do that, but CLOSERS should as well. Nothing is to say that CtoM cant be or shouldn't be your closer.
Now for new opener ideas.
Red Hot Momma (Chicago Surprise/Opener) is tested and proved, and is an amazing opener.
Perhaps a 1 strong phased, or 3 phased sandwich routine.
In regards to your use of gaffs... gaffs can be great, but don't get too tied down by them. FASDIU tricks will be your best bet to fall back on, so make sure that FASIU tricks are your bread and butter. It will serve you better in the long run.
And lastly, if you are performing at school, "less is better" holds true. I would cut everything down to rare performances of a set of TWO tricks. No more. Save some material for the next day / week/ month even.