I (17y/o) have been developing a rocket launch simulation that allows the user to explore what it's like launching a rocket from earth and putting it into orbit. This idea originally started as an educational simulation but as i've gone more down the rabbit hole the more i've wanted to make it realistic. The problem is that I've never had a formal orbital mechanics class or anything like that so I don't know what I'm missing, what I currently have implemented is:

  Variable gravity
  Variable Atmospheric drag (US Standard Atmosphere 1976)
  Multi-stage rockets
  Closed-loop guidance / pitch programs (works well within ranges 350km to 600km)
  Orbital prediction and thrusting options to change your orbit.

The feedback I'm looking for is: UI improvements and possible future physics implementations that I can work on.

Current code and physics can be found at: https://github.com/donutTheJedi/Rocket-Launch-Simulation