Since you have posted here, I think you already really want to shave. Like others have said, you still have a lot of hair. I was in a similar position and wanted to shave at my first signs of thinning and I did. My thinning continued and I have little hair left on top, but I never really had to deal with balding since I had already started shaving.
So go with the shorter haircut, and by spring you will have more courage to shave it. The reality is, no body really cares. You will get a few comment, but you will get those for any change.