If I were to do this project again I would make sure everything was on par with what it had to be. I would also procrastinate less and make sure the payload was ready promptly before the launch day with everything working and ready to record. I would test different weights and see what would happen if the weight was above or below the limit to see how it would affect the flight patterns of the balloon and payload. I would use some other instruments and test other objects to see what happens if you put other objects twenty miles into the atmosphere. I might test a different type of balloon with other gas or make the payload out of different material. I might also have tested the altitude to see what the maximum altitude the balloon could reach and see if the instruments still worked properly.