Tell your tutor that scratches become spots for rust. Rust ruins the frames over time and the frame is the most expensive part of a bike.
You may want to look into a soft plastic or hard rubber coating on the tube and lock. Neoprene may not last long with lots of use.
My only other suggestion is make the lock need power to unlock. If anything happens to the power supply the bike stays securely locked. Another benefit is that you use less power overall since your not using power while locked or not in use. This should also allow the electro magnet to last longer since it is not powered all the time.